Airbag trigger unit Cayenne S 4,5 l V8

[Alexander Tobiasson]

Probably my Airbag Trigger Unit defective. I have had the error code 1738 in almost 1 year now and no one can help mig.Har been in contact with the Porsche Center and I have replaced the airbag sensor to a new but the problem remains. I have also checked all the cables and splices.

[Loren]

Fault code 1738

 

Possible cause of fault

- Implausible signal (incorrect airbag sensor installed)

- Open circuit (based on wiring between airbag triggering unit and airbag sensor or the airbag sensor itself)

- Electrical fault in electric circuit (based on wiring between airbag triggering unit and airbag sensor; probably a short circuit to B+ or a short circuit to ground)

- Faulty (airbag sensor is faulty)

- Airbag triggering unit faulty

 

Note: The six installed sensors have an identical design of wiring harness contact plug. Only the mounting points are different. The airbag sensors under the driver's and passenger's seats have a thread for fastening, while all the other sensors only have a non-threaded bushing. There is therefore a risk of confusing the sensors on the rear wheel arches with the sensors on the lock mount. If these are confused accidentally, the 9588 Porsche System Tester ll will display this fault code along with the fault type 'implausible signal'. Given this, it is always important to ensure that the correct sensors are installed at the correct position. This is because they have different sensitivity settings.

[Alexander Tobiasson]

We have measured and checked the wiring between the airbag sensor and airbag triggering unit. Nothing. We have followed Porsche's steps and your recommendations you have written here. Porshes own diagnostic system indicates the same error on Porshe Center workshop. Porsche Center recommend me to buy a new airbag Trigger Unit. They do not guarantee that this is the problem. Unfortunately I have not the financial means to buy a new box. Can you buy a used airbag Trigger Unit Box from the same model year (2004)?

[Loren]

Yes, you can buy a used (hopefully good) airbag control unit and use it.

[Alexander Tobiasson]

Yes, you can buy a used (hopefully good) airbag control unit and use it.

Thank you Loren. How important is it with all number ranges that are printed on the boxes? It is sufficient that the part number is identical, or must all number combinations on the boxes to be identical? If I have received accurate information, this number is important in the box. 3D0 909 601D. Thankful for all the support

[Loren]

There were at lest 3 revisions of the airbag control unit - so best stick with the same part number.

[Alexander Tobiasson]

There were at lest 3 revisions of the airbag control unit - so best stick with the same part number.

Hi Loren. Are you able to look at my picture I've attached in this thread? I would appreciate if you are able to tell you which number combinations to match. I have managed to find a couple of boxes on ebay but are unsure which numbers must conform? Have found a box where all the numbers shown true except that which stands between the "stars"

 

With respect / Alex, Sweden

[JFP in PA]

 

There were at lest 3 revisions of the airbag control unit - so best stick with the same part number.

Hi Loren. Are you able to look at my picture I've attached in this thread? I would appreciate if you are able to tell you which number combinations to match. I have managed to find a couple of boxes on ebay but are unsure which numbers must conform? Have found a box where all the numbers shown true except that which stands between the "stars"

 

With respect / Alex, Sweden

 

 

The new box must have all the same exact same part numbers as your original unit.

[Loren]

 

There were at lest 3 revisions of the airbag control unit - so best stick with the same part number.

Hi Loren. Are you able to look at my picture I've attached in this thread? I would appreciate if you are able to tell you which number combinations to match. I have managed to find a couple of boxes on ebay but are unsure which numbers must conform? Have found a box where all the numbers shown true except that which stands between the "stars"

 

With respect / Alex, Sweden

 

 

Between the stars is the serial number - the large number is the part number. The part numbers MUST match.

[Alexander Tobiasson]

 

 

There were at lest 3 revisions of the airbag control unit - so best stick with the same part number.

Hi Loren. Are you able to look at my picture I've attached in this thread? I would appreciate if you are able to tell you which number combinations to match. I have managed to find a couple of boxes on ebay but are unsure which numbers must conform? Have found a box where all the numbers shown true except that which stands between the "stars"

 

With respect / Alex, Sweden

 

 

The new box must have all the same exact same part numbers as your original unit.

 

all the numbers on the box must therefore match?

[JFP in PA]

 

 

 

There were at lest 3 revisions of the airbag control unit - so best stick with the same part number.

Hi Loren. Are you able to look at my picture I've attached in this thread? I would appreciate if you are able to tell you which number combinations to match. I have managed to find a couple of boxes on ebay but are unsure which numbers must conform? Have found a box where all the numbers shown true except that which stands between the "stars"

 

With respect / Alex, Sweden

 

 

The new box must have all the same exact same part numbers as your original unit.

 

all the numbers on the box must therefore match?

 

 

The part number must match exactly, the serial numbers (between the * *) are unique to each box and all are different.

[Alexander Tobiasson]

 

 

 

 

There were at lest 3 revisions of the airbag control unit - so best stick with the same part number.

Hi Loren. Are you able to look at my picture I've attached in this thread? I would appreciate if you are able to tell you which number combinations to match. I have managed to find a couple of boxes on ebay but are unsure which numbers must conform? Have found a box where all the numbers shown true except that which stands between the "stars"

 

With respect / Alex, Sweden

 

 

The new box must have all the same exact same part numbers as your original unit.

 

all the numbers on the box must therefore match?

 

 

The part number must match exactly, the serial numbers (between the * *) are unique to each box and all are different.

 

What you're trying to say is that finding a used identical box is impossible?

[JFP in PA]

 

 

 

 

 

There were at lest 3 revisions of the airbag control unit - so best stick with the same part number.

Hi Loren. Are you able to look at my picture I've attached in this thread? I would appreciate if you are able to tell you which number combinations to match. I have managed to find a couple of boxes on ebay but are unsure which numbers must conform? Have found a box where all the numbers shown true except that which stands between the "stars"

 

With respect / Alex, Sweden

 

 

The new box must have all the same exact same part numbers as your original unit.

 

all the numbers on the box must therefore match?

 

 

The part number must match exactly, the serial numbers (between the * *) are unique to each box and all are different.

 

What you're trying to say is that finding a used identical box is impossible?

 

 

No, I am not.  Using your picture above:

 

 

You have to find one with the exact same 3D0 909 601 D part number; the serial number (*0036 Q 002CM1T*) is does not matter as the only one with that number is the one in your photo.

[Alexander Tobiasson]

 

 

 

 

 

 

There were at lest 3 revisions of the airbag control unit - so best stick with the same part number.

Hi Loren. Are you able to look at my picture I've attached in this thread? I would appreciate if you are able to tell you which number combinations to match. I have managed to find a couple of boxes on ebay but are unsure which numbers must conform? Have found a box where all the numbers shown true except that which stands between the "stars"

 

With respect / Alex, Sweden

 

 

The new box must have all the same exact same part numbers as your original unit.

 

all the numbers on the box must therefore match?

 

 

The part number must match exactly, the serial numbers (between the * *) are unique to each box and all are different.

 

What you're trying to say is that finding a used identical box is impossible?

 

 

No, I am not.  Using your picture above:

 

 

You have to find one with the exact same 3D0 909 601 D part number; the serial number (*0036 Q 002CM1T*) is does not matter as the only one with that number is the one in your photo.

 

I apologize if I'm nagging. I'm just trying to learn as much about my box as possible. However, you can clarify your last post, I would be very grateful. it is enough that I can find a box from a Porsche Cayenne S 4,5l 2004 model with the same 3D0 909 601 D Part Number. The serial number is thus unique to each box and is only one of each?

[JFP in PA]

 

 

 

 

 

 

 

There were at lest 3 revisions of the airbag control unit - so best stick with the same part number.

Hi Loren. Are you able to look at my picture I've attached in this thread? I would appreciate if you are able to tell you which number combinations to match. I have managed to find a couple of boxes on ebay but are unsure which numbers must conform? Have found a box where all the numbers shown true except that which stands between the "stars"

 

With respect / Alex, Sweden

 

 

The new box must have all the same exact same part numbers as your original unit.

 

all the numbers on the box must therefore match?

 

 

The part number must match exactly, the serial numbers (between the * *) are unique to each box and all are different.

 

What you're trying to say is that finding a used identical box is impossible?

 

 

No, I am not.  Using your picture above:

 

 

You have to find one with the exact same 3D0 909 601 D part number; the serial number (*0036 Q 002CM1T*) is does not matter as the only one with that number is the one in your photo.

 

I apologize if I'm nagging. I'm just trying to learn as much about my box as possible. However, you can clarify your last post, I would be very grateful. it is enough that I can find a box from a Porsche Cayenne S 4,5l 2004 model with the same 3D0 909 601 D Part Number. The serial number is thus unique to each box and is only one of each?

 

 

That is correct.  The serial numbers are unique to each box, so they do not matter, you just want to exactly match the part number.

[Alexander Tobiasson]

 

 

 

 

 

 

 

 

There were at lest 3 revisions of the airbag control unit - so best stick with the same part number.

Hi Loren. Are you able to look at my picture I've attached in this thread? I would appreciate if you are able to tell you which number combinations to match. I have managed to find a couple of boxes on ebay but are unsure which numbers must conform? Have found a box where all the numbers shown true except that which stands between the "stars"

 

With respect / Alex, Sweden

 

 

The new box must have all the same exact same part numbers as your original unit.

 

all the numbers on the box must therefore match?

 

 

The part number must match exactly, the serial numbers (between the * *) are unique to each box and all are different.

 

What you're trying to say is that finding a used identical box is impossible?

 

 

No, I am not.  Using your picture above:

 

 

You have to find one with the exact same 3D0 909 601 D part number; the serial number (*0036 Q 002CM1T*) is does not matter as the only one with that number is the one in your photo.

 

I apologize if I'm nagging. I'm just trying to learn as much about my box as possible. However, you can clarify your last post, I would be very grateful. it is enough that I can find a box from a Porsche Cayenne S 4,5l 2004 model with the same 3D0 909 601 D Part Number. The serial number is thus unique to each box and is only one of each?

 

 

That is correct.  The serial numbers are unique to each box, so they do not matter, you just want to exactly match the part number.

 

I appoint you to my everyday hero. Thanks for your time and dedication to my problem. Greatly appreciated! with the best porsche greetings Alexander Tobiasson, Sweden

[JFP in PA]

 

 

 

 

 

 

 

 

 

There were at lest 3 revisions of the airbag control unit - so best stick with the same part number.

Hi Loren. Are you able to look at my picture I've attached in this thread? I would appreciate if you are able to tell you which number combinations to match. I have managed to find a couple of boxes on ebay but are unsure which numbers must conform? Have found a box where all the numbers shown true except that which stands between the "stars"

 

With respect / Alex, Sweden

 

 

The new box must have all the same exact same part numbers as your original unit.

 

all the numbers on the box must therefore match?

 

 

The part number must match exactly, the serial numbers (between the * *) are unique to each box and all are different.

 

What you're trying to say is that finding a used identical box is impossible?

 

 

No, I am not.  Using your picture above:

 

 

You have to find one with the exact same 3D0 909 601 D part number; the serial number (*0036 Q 002CM1T*) is does not matter as the only one with that number is the one in your photo.

 

I apologize if I'm nagging. I'm just trying to learn as much about my box as possible. However, you can clarify your last post, I would be very grateful. it is enough that I can find a box from a Porsche Cayenne S 4,5l 2004 model with the same 3D0 909 601 D Part Number. The serial number is thus unique to each box and is only one of each?

 

 

That is correct.  The serial numbers are unique to each box, so they do not matter, you just want to exactly match the part number.

 

I appoint you to my everyday hero. Thanks for your time and dedication to my problem. Greatly appreciated! with the best porsche greetings Alexander Tobiasson, Sweden

 

 

Tack. ;)

[Alexander Tobiasson]

Has now changed airbag trigger unit (box) with no results. I have changed everything in the manual for error code 1738. New airbag tendons, new airbag triggering unit box. But my airbag light will remain illuminated. I have tried to zero the system with PIWIS. Unfortunately, my intuition told from the beginning that the error is in a ground fault. I have spent one year at this error and give up now. The car does not go through the Swedish survey and I have now immobilize the car. I will not be able to sell the car even with this problem. I feel very distressed and dejected ...

[JFP in PA]

Has now changed airbag trigger unit (box) with no results. I have changed everything in the manual for error code 1738. New airbag tendons, new airbag triggering unit box. But my airbag light will remain illuminated. I have tried to zero the system with PIWIS. Unfortunately, my intuition told from the beginning that the error is in a ground fault. I have spent one year at this error and give up now. The car does not go through the Swedish survey and I have now immobilize the car. I will not be able to sell the car even with this problem. I feel very distressed and dejected ...

 

Have you checked the grounds on the seat belt buckles?  They are well known for ground related faults.

[Alexander Tobiasson]

 

Has now changed airbag trigger unit (box) with no results. I have changed everything in the manual for error code 1738. New airbag tendons, new airbag triggering unit box. But my airbag light will remain illuminated. I have tried to zero the system with PIWIS. Unfortunately, my intuition told from the beginning that the error is in a ground fault. I have spent one year at this error and give up now. The car does not go through the Swedish survey and I have now immobilize the car. I will not be able to sell the car even with this problem. I feel very distressed and dejected ...

 

Have you checked the grounds on the seat belt buckles?  They are well known for ground related faults.

 

No, this was new information for me. Where can I find it / them ???

[JFP in PA]

 

 

Has now changed airbag trigger unit (box) with no results. I have changed everything in the manual for error code 1738. New airbag tendons, new airbag triggering unit box. But my airbag light will remain illuminated. I have tried to zero the system with PIWIS. Unfortunately, my intuition told from the beginning that the error is in a ground fault. I have spent one year at this error and give up now. The car does not go through the Swedish survey and I have now immobilize the car. I will not be able to sell the car even with this problem. I feel very distressed and dejected ...

 

Have you checked the grounds on the seat belt buckles?  They are well known for ground related faults.

 

No, this was new information for me. Where can I find it / them ???

 

 

The seat belt buckles, the part that the shoulder harness plugs into, have wires running to them that tell the system when the seat belts are buckled and turn off the seat belt alert chimes.  They also help tell the air bag system which seats are occupied in case of a crash, as well as controlling the system pre-tensioners.  If the buckles get dirt in them, they often do not register properly and the air bag system declares a fault.

 

 

Sometimes, but not always, just cleaning out the buckles with some electrical contact cleaner will solve the issue, other times the buckle and/or wiring harness need to be replaced as wear has broken the circuit.

[Alexander Tobiasson]

 

 

 

Has now changed airbag trigger unit (box) with no results. I have changed everything in the manual for error code 1738. New airbag tendons, new airbag triggering unit box. But my airbag light will remain illuminated. I have tried to zero the system with PIWIS. Unfortunately, my intuition told from the beginning that the error is in a ground fault. I have spent one year at this error and give up now. The car does not go through the Swedish survey and I have now immobilize the car. I will not be able to sell the car even with this problem. I feel very distressed and dejected ...

 

Have you checked the grounds on the seat belt buckles?  They are well known for ground related faults.

 

No, this was new information for me. Where can I find it / them ???

 

 

The seat belt buckles, the part that the shoulder harness plugs into, have wires running to them that tell the system when the seat belts are buckled and turn off the seat belt alert chimes.  They also help tell the air bag system which seats are occupied in case of a crash, as well as controlling the system pre-tensioners.  If the buckles get dirt in them, they often do not register properly and the air bag system declares a fault.

 

 

Sometimes, but not always, just cleaning out the buckles with some electrical contact cleaner will solve the issue, other times the buckle and/or wiring harness need to be replaced as wear has broken the circuit.

 

ok'll check it tomorrow. If there is a Porsche god, show that you exist tomorrow and say that this is my fault !!!

[Alexander Tobiasson]

 

 

 

Has now changed airbag trigger unit (box) with no results. I have changed everything in the manual for error code 1738. New airbag tendons, new airbag triggering unit box. But my airbag light will remain illuminated. I have tried to zero the system with PIWIS. Unfortunately, my intuition told from the beginning that the error is in a ground fault. I have spent one year at this error and give up now. The car does not go through the Swedish survey and I have now immobilize the car. I will not be able to sell the car even with this problem. I feel very distressed and dejected ...

 

Have you checked the grounds on the seat belt buckles?  They are well known for ground related faults.

 

No, this was new information for me. Where can I find it / them ???

 

 

The seat belt buckles, the part that the shoulder harness plugs into, have wires running to them that tell the system when the seat belts are buckled and turn off the seat belt alert chimes.  They also help tell the air bag system which seats are occupied in case of a crash, as well as controlling the system pre-tensioners.  If the buckles get dirt in them, they often do not register properly and the air bag system declares a fault.

 

 

Sometimes, but not always, just cleaning out the buckles with some electrical contact cleaner will solve the issue, other times the buckle and/or wiring harness need to be replaced as wear has broken the circuit.

 

I have tried to clean but it does not help. I have noticed that the warning lamp for the "safety belt" is not lit when driving without a seat belt. The warning light does not indicate when starting the car. I have never seen the light shine sometime?

[JFP in PA]

 

 

 

 

Has now changed airbag trigger unit (box) with no results. I have changed everything in the manual for error code 1738. New airbag tendons, new airbag triggering unit box. But my airbag light will remain illuminated. I have tried to zero the system with PIWIS. Unfortunately, my intuition told from the beginning that the error is in a ground fault. I have spent one year at this error and give up now. The car does not go through the Swedish survey and I have now immobilize the car. I will not be able to sell the car even with this problem. I feel very distressed and dejected ...

 

Have you checked the grounds on the seat belt buckles?  They are well known for ground related faults.

 

No, this was new information for me. Where can I find it / them ???

 

 

The seat belt buckles, the part that the shoulder harness plugs into, have wires running to them that tell the system when the seat belts are buckled and turn off the seat belt alert chimes.  They also help tell the air bag system which seats are occupied in case of a crash, as well as controlling the system pre-tensioners.  If the buckles get dirt in them, they often do not register properly and the air bag system declares a fault.

 

 

Sometimes, but not always, just cleaning out the buckles with some electrical contact cleaner will solve the issue, other times the buckle and/or wiring harness need to be replaced as wear has broken the circuit.

 

I have tried to clean but it does not help. I have noticed that the warning lamp for the "safety belt" is not lit when driving without a seat belt. The warning light does not indicate when starting the car. I have never seen the light shine sometime?

 

 

It is sounding more like you have a buckle or wiring  issue, you should get an indication and/or a audio alarm of some sort if you try driving without the seat belt.

[Alexander Tobiasson]

 

 

 

 

 

Has now changed airbag trigger unit (box) with no results. I have changed everything in the manual for error code 1738. New airbag tendons, new airbag triggering unit box. But my airbag light will remain illuminated. I have tried to zero the system with PIWIS. Unfortunately, my intuition told from the beginning that the error is in a ground fault. I have spent one year at this error and give up now. The car does not go through the Swedish survey and I have now immobilize the car. I will not be able to sell the car even with this problem. I feel very distressed and dejected ...

 

Have you checked the grounds on the seat belt buckles?  They are well known for ground related faults.

 

No, this was new information for me. Where can I find it / them ???

 

 

The seat belt buckles, the part that the shoulder harness plugs into, have wires running to them that tell the system when the seat belts are buckled and turn off the seat belt alert chimes.  They also help tell the air bag system which seats are occupied in case of a crash, as well as controlling the system pre-tensioners.  If the buckles get dirt in them, they often do not register properly and the air bag system declares a fault.

 

 

Sometimes, but not always, just cleaning out the buckles with some electrical contact cleaner will solve the issue, other times the buckle and/or wiring harness need to be replaced as wear has broken the circuit.

 

I have tried to clean but it does not help. I have noticed that the warning lamp for the "safety belt" is not lit when driving without a seat belt. The warning light does not indicate when starting the car. I have never seen the light shine sometime?

 

 

It is sounding more like you have a buckle or wiring  issue, you should get an indication and/or a audio alarm of some sort if you try driving without the seat belt.

 

I have tried to clean but it does not help. I have noticed that the warning lamp for the "safety belt" is not lit when driving without a seat belt. The warning light does not indicate when starting the car. I have never seen the light shine sometime?