Fuel Gauge Reading

[Kevin M.]

I recently switched out my cluster for one with aluminum dials.. I didn't have time to take it to the dealer to get re-programmed for the miles.. so I switched it myself.. While I was at the Concours in Monterey I had a 1/4 of tank left and almost ran out of gas.. So obviously the new cluster's gauge is a little off. I recall there is a way that the dealer can change the gauge from going through the first half of the tank faster then the last half of the tank.. (which is how mine currently is) Is there a setting in the cluster programmed by the dealer? Going through the 2nd tank of gas was the same scenario, I filled up at 1/4 of tank.. and it was really on E

Any thoughts?

[Loren]

I seem to recall that the issue is disconnecting the battery (or in this case the instrument cluster computer) with 1/4 or less tank of gas. I think the way to fix it is to fill the tank -- disconnect the battery for a few minutes then reconnect the battery.

[David (Va)]

FUEL LEVEL DISPLAY

Problem

If the power supply is interrupted by a discharged or disconnected battery with the tank containing less than 19 I, the calculated value for the range on remaining fuel in the instrument cluster will be incorrect or deleted.

If the tank contains less than 10 I, it is possible that the fuel level warning light is no longer activated.

If the power supply is restored with the fuel level at less than 19 I, it is possible that the fuel level display may subsequently display too much.

This may lead to the vehicle breaking down.

Remedy

Refill at least 19 I of fuel; then the fuel level sensor is in operating range and its display precision is guaranteed.

[Tool Pants]

I spoke to Peter not knowing what car you have or what car the cluster was made for.

He said if you have a C2 and put in a cluster for a C4 that is what will happen. Jeff

[Kevin M.]

Well I will try to refill then disconnect the battery...

Tool Pants so there are 2 different part numbers for a C2 or C4?

Anyone know the part numbers for the C2 or C4?

[Loren]

Well I will try to refill then disconnect the battery...

Tool Pants so there are 2 different part numbers for a C2 or C4?

Anyone know the part numbers for the C2 or C4?

Yes, C2 and C4 have different numbers.

There are several for each.

C2 numbers start with: 996 641 103 02 or 996 641 104 03 etc.

and

C4 numbers start with: 996 641 113 03 or 996 641 114 03 etc.

[Tool Pants]

Peter said the software in a C4 cluster is different than a C2, assuming your new cluster is from a C4 and that your car is a C2, and it cannot be changed or recalibrated with the PST2.

Hope the battery disconnect works. If not, then you can swap instrument cluster parts if you still have your original cluster. Jeff

[Kevin M.]

Good Info! Thanks Jeff. I do still have the original Cluster.. I will pull out the new one and check the part numbers with the ones Loren Supplied..

Changing out the the parts doesn't look to difficult or is it?

[Loren]

I will pull out the new one and check the part numbers with the ones Loren Supplied..

Kevin,

The part numbers I gave you were the pattern examples. As I said there are several part numbers. Why don't you give us part numbers for the old and new and then we can check what model they are for?

Thanks!

[Kevin M.]

The old cluster has part number of.. 996 641 103 01 70

The new one had this part number on the box 996 641 982 46 70C

[Tool Pants]

Your new cluster is for a C4. Lucky guess, I guess. 480 is the code for 6 speed. 484 is the code for USA. C4 is the code for....... Jeff

[Kevin M.]

Jeff.. so exactly what parts would I have to switch out? Just the dials?.... Suggestions please :)

[Tool Pants]

Put the green circuit board from your C2 into the C4 cluster. Or your C4 dial assembly in the C2 cluster. Either way you will see what you saw on your orignial C2 cluster except the dials will be white.

There are about 3 companies aftermarket companies that claim they can modify the chips in the cluster, for the mileage. Have no idea if they can do anything with the fuel level.

[Kevin M.]

Great thanks Jeff..I'll let you know what I end up doing....

[Kevin M.]

Well that worked Jeff, The fuel gauge is back to normal!! Save me a trip to the dealer as well... didn't have to change out the miles.. Also something else that was intersting on the C4 Cluster.. the ABS & Brake Fluid lights were on.. and went off when the C2 Cluster brain went back in... Thanks for your tips!!

Edited September 18, 2003 by Kevin M.

[David80]

I think I may have screwed up and am looking for some advice/guidance.  I have a 2001 C2 (with black dials) and mistakenly purchased the instrument cluster from a 1999 C4 (with silver dials).  My intent was to disassemble both instrument clusters (into the three component sections) and cobble together the two front sections of the C4 cluster (the cover/facia and the dials) with my existing section three (the part with the connectors that contains the odometer reading).  Will this work...or am I going to have compatibility issues (like the fuel tank reading)?  Thanks.

[Loren]

1 hour ago, David80 said:

I think I may have screwed up and am looking for some advice/guidance.  I have a 2001 C2 (with black dials) and mistakenly purchased the instrument cluster from a 1999 C4 (with silver dials).  My intent was to disassemble both instrument clusters (into the three component sections) and cobble together the two front sections of the C4 cluster (the cover/facia and the dials) with my existing section three (the part with the connectors that contains the odometer reading).  Will this work...or am I going to have compatibility issues (like the fuel tank reading)?  Thanks.

 

If your car is a MY2001 then you have the wrong instrument cluster.

The cluster (electrical) design changed in 2001 (and again in 2002). So  MY2001 cars are unique.

 

Other than that clusters are different by both 2 wheel drive vs 4 wheel drive - as well as 6 speed vs Tiptronic. You need to make sure those are correct also.

 

If you just want to change dial color - there are kits for that.

[David80]

1 hour ago, Loren said:

 

If your car is a MY2001 then you have the wrong instrument cluster.

The cluster (electrical) design changed in 2001 (and again in 2002). So  MY2001 cars are unique.

 

Other than that clusters are different by both 2 wheel drive vs 4 wheel drive - as well as 6 speed vs Tiptronic. You need to make sure those are correct also.

 

If you just want to change dial color - there are kits for that.

Loren,  thanks for the quick reply.  I understand there's a difference between the Tiptronic and 6-speed (not a factor here--I have a cluster for a 6-speed..which is what my car is) and that the electrical design is different depending on the MY.  My question is, however, since I am only interested in the dials themselves and in maintaining the correct odometer reading for my car, surely the dials should still be compatible when I mate them to the LCD portion of my existing cluster?  In essence (using the attached image), I want to take Parts A and B from the C4 cluster and mate them to the Part C of my C2's cluster.    Yes, I realize there are other ways/kits to change the faces on the dials, and I may resort to that...but in the meantime, I'd like to solve this technical conundrum.  Thanks again.

[Loren]

Your guess is as good as mine - electrically they are different.

I would opt for a dial kit since that is your goal - you may just smoke both clusters trying.

[David80]

43 minutes ago, Loren said:

Your guess is as good as mine - electrically they are different.

I would opt for a dial kit since that is your goal - you may just smoke both clusters trying.

Loren, you're the definition of optimism (not), ha ha.  I had hoped your "guess" would be better than mine.  My guess was that Porsche wouldn't spend a ton of money designing, developing and manufacturing a different set of dials every year, especially parts that look interchangeable (and in fact, are interchangeable, even with Boxsters).  I had read that 996 clusters were basically the same until 2003 or 2004, when the Part C did change (the way it's attached, as well as the three different electrical connectors/jacks on the rear), and I had also read that there was a difference between the C4 and C2 fuel sending units that would affect compatibility, so Part C's are obviously electrically different...but the gauges themselves?  I'm gonna take a leap (and maybe sacrifice myself for the good of the community) and bank on my assumption (a dangerous word, I know) that Porsche is basically greedy and only "innovates" when it has to, so it has many interchangeable parts from one year to the next, and even between models, and see what happens.  Wish me luck.  I'll keep you (and all interested parties reading this) posted. 

Edited November 28, 2017 by David80
Typos (my OCD)

[David80]

Loren, okay, you convinced me (hardheaded, yes; incapable of learning, no) and have decided to install new faces on my dials.  Since I had a spare cluster available, I decided to try taking it apart to see how difficult the job would be.  Turns out it's relatively simple (but delicate) work.  Here's my question, When I took the needles off and then reinstalled them, I notice that the speedo and tach needles move freely (i.e., well below where the 0 would be and well beyond where the upper MPH or RPM would be).  Here's my question: I thought I was careful, but did I break something?  Or...maybe I just need to ensure the needles are aligned (at 0, or their previous mark) when I install and power up.  Finally, I have seen a ton of videos where people did not disconnect the battery to remove the cluster and suffered no ill affects.  While I realize it's the safest thing to do, is there a problem leaving the battery connected?  Thanks for your advice.

Edited December 7, 2017 by David80
Accuracy.

[Loren]

I would say no power to reduce the risk of damaging a sensitive/delicate dial drives.

It is very important to accurately mark the needle positions prior to removing them. If you don't then you will likely have to go to a speedo repair shop and have them re-calibrate the gauges.

[David80]

Thanks.