1999 Carrera Cab w/Tip, total loss of electric power.

[nhobx]

1999 Cab,Tiptronic, 28K miles, original owner, never any damage. Today removed instrument cluster to inspect non-functioning oil pressure gauge (hasn't worked in 5 years)then reconnected module plugs and started car to make sure everything functioning properly before positioning instrument module and reinstalling 2 dash screws. Everything fine until the emergency flasher became intermittent (would stick on, then would turn off when wires to flasher were touched). Heard strange high pitch alarm sound coming from dash instrument cluster when flasher wires were touched, then suddenly car stopped running with total loss of electric power. Now have no indication of power when turning the key in ignition. Both hood locks froze, so put jumper wire in main fuse block slot c3 as is done when battery is dead and hood lock cannot be opened, applied direct 12v power to jumper, hood locks unfroze,got all dash panel indicator lights on but still no engine crank. Removed direct 12v power from fuse block and now again have no power whatsoever. I do have a good battery (tested and verified). Tried jump starting with 12v power applied directly to the 12v jump start post on the engine and also nothing. Removed, inspected, reinstalled every fuse in main fuse block. I am totally stumped, having searched the internet for hours trying to find out what to do next. Is the emergency flasher module required to be functioning properly for electric power continuity and engine start? I am thinking perhaps if the flasher module is now bad, that may be the cause, but I have no way of testing module. I have copy of shop repair manual but found nothing in it to help me trouble-shoot this.

Had similar thing happen a couple of months ago. Turned key on and did not have any power. When checking the battery condition, I noticed a multi-wire connector block had disconnected from horn next to the battery(if that isn't the horn, then I just revealed/verified my ignorance. Reconnected the block and then everything was ok again. This was the first thing I looked at when losing power this time, but it remains properly connected.

Don't know if it has relevance, but for last several months I have heard buzzing noise through left speaker on dash after engine start. The buzzing sound would go up and down with engine revs. Could hear noise in speaker even with radio turned off. Really aggravating, but would be willing to hear it now as it would mean the car is started!

BTW, I am more than 100 miles from nearest Porsche dealer (under normal conditions I usually consider this to be a safe distance).

I do not have specialized test equipment

Any serious suggestions?

[logray]

Did you check the fuses under the carpet behind the rear seats?

Assuming your batt is good.

If that doesnt work...

Try unplugging the inst cluster and see what you get.

[1schoir]

1999 Cab,Tiptronic, 28K miles, original owner, never any damage. Today removed instrument cluster to inspect non-functioning oil pressure gauge (hasn't worked in 5 years)then reconnected module plugs and started car to make sure everything functioning properly before positioning instrument module and reinstalling 2 dash screws. Everything fine until the emergency flasher became intermittent (would stick on, then would turn off when wires to flasher were touched). Heard strange high pitch alarm sound coming from dash instrument cluster when flasher wires were touched, then suddenly car stopped running with total loss of electric power. Now have no indication of power when turning the key in ignition. Both hood locks froze, so put jumper wire in main fuse block slot c3 as is done when battery is dead and hood lock cannot be opened, applied direct 12v power to jumper, hood locks unfroze,got all dash panel indicator lights on but still no engine crank. Removed direct 12v power from fuse block and now again have no power whatsoever. I do have a good battery (tested and verified). Tried jump starting with 12v power applied directly to the 12v jump start post on the engine and also nothing. Removed, inspected, reinstalled every fuse in main fuse block. I am totally stumped, having searched the internet for hours trying to find out what to do next. Is the emergency flasher module required to be functioning properly for electric power continuity and engine start? I am thinking perhaps if the flasher module is now bad, that may be the cause, but I have no way of testing module. I have copy of shop repair manual but found nothing in it to help me trouble-shoot this.

Had similar thing happen a couple of months ago. Turned key on and did not have any power. When checking the battery condition, I noticed a multi-wire connector block had disconnected from horn next to the battery(if that isn't the horn, then I just revealed/verified my ignorance. Reconnected the block and then everything was ok again. This was the first thing I looked at when losing power this time, but it remains properly connected.

Don't know if it has relevance, but for last several months I have heard buzzing noise through left speaker on dash after engine start. The buzzing sound would go up and down with engine revs. Could hear noise in speaker even with radio turned off. Really aggravating, but would be willing to hear it now as it would mean the car is started!

BTW, I am more than 100 miles from nearest Porsche dealer (under normal conditions I usually consider this to be a safe distance).

I do not have specialized test equipment

Any serious suggestions?

I am not sure that it would apply in this case from your description of how the problem originated (i.e., wires behind emergency flasher), but on all of the 986's and 996's, the electrical portion of the ignition switch is a frequent failure point, and it causes some otherwise inexplicable electrical gremlins.

Since the part is so inexpensive (about $10, and it's an Audi part, part number 4A0 905 849 B) and relatively easy DIY to replace, it may be worth a shot to eliminate that as a possible source of the problem.

Regards, Maurice.

[nhobx]

Did you check the fuses under the carpet behind the rear seats?

Assuming your batt is good.

If that doesnt work...

Try unplugging the inst cluster and see what you get.

Thank you Logray for the quick reply. Removed carpeted panel behind rear seats. Did not find any fuses. Unplugged instrument cluster, still nothing.

[logray]

It's been a while since I was behind the rear seat, now that I think about it the 40amp fuse(es?) there, at least the one there might be just for the secondary air pump/SAI???

Anyways, +1 on the previous post about the ignition switch, a common issue and might be an inexpensive place to start....

After that (or even now) I would start poking around with a multi meter at relays and various points of the car, such as DME, engine, alarm module, instrument panel, etc.

Once on a VW quantum I literally burnt/smoked a wire all the way through into the instrument cluster. Car wouldn't start as there was damage to a lot of places under the dash, and I had to replace the instrument cluster and other components. I forgot to disconnect the battery before doing this work. Lesson learned!

Edited April 23, 2011 by logray

[Loren]

Did you check the fuses under the carpet behind the rear seats?

Assuming your batt is good.

If that doesnt work...

Try unplugging the inst cluster and see what you get.

Thank you Logray for the quick reply. Removed carpeted panel behind rear seats. Did not find any fuses. Unplugged instrument cluster, still nothing.

The fuses are on the relay 2 tray - you need to loosen the two nuts on the tray and flip it over for access.

[nhobx]

Thank you Maurice, you were spot on with the ignition switch. However, I was unaware the switch comes with either a black or white housing, each carrying the same part number, but each having a different shape and length of housing. Naturally, only one will be the correct fit depending on the year of car. According to the dealer, my '99 Carrera takes the black one, which he gladly supplied me for $55 and change. After my 200+ mile round trip back home (using a different car)I removed the faulty switch and much to my surprise, it was a white body switch. Frustrated, I then went on ebay and bought a white switch for $17 including free shipping. According to all information I have been able to find on the internet, the white switch became standard in either 2004, or 2005 model Carerras. This is really confusing to me as I am the original owner of this car and have never had the switch replaced. Anyway, after receiving the white switch, it installed easily and the car started without any further issues. Thank you once again, and thank you to everyone that provided input that helped me troubleshoot this nightmare.

1999 Cab,Tiptronic, 28K miles, original owner, never any damage. Today removed instrument cluster to inspect non-functioning oil pressure gauge (hasn't worked in 5 years)then reconnected module plugs and started car to make sure everything functioning properly before positioning instrument module and reinstalling 2 dash screws. Everything fine until the emergency flasher became intermittent (would stick on, then would turn off when wires to flasher were touched). Heard strange high pitch alarm sound coming from dash instrument cluster when flasher wires were touched, then suddenly car stopped running with total loss of electric power. Now have no indication of power when turning the key in ignition. Both hood locks froze, so put jumper wire in main fuse block slot c3 as is done when battery is dead and hood lock cannot be opened, applied direct 12v power to jumper, hood locks unfroze,got all dash panel indicator lights on but still no engine crank. Removed direct 12v power from fuse block and now again have no power whatsoever. I do have a good battery (tested and verified). Tried jump starting with 12v power applied directly to the 12v jump start post on the engine and also nothing. Removed, inspected, reinstalled every fuse in main fuse block. I am totally stumped, having searched the internet for hours trying to find out what to do next. Is the emergency flasher module required to be functioning properly for electric power continuity and engine start? I am thinking perhaps if the flasher module is now bad, that may be the cause, but I have no way of testing module. I have copy of shop repair manual but found nothing in it to help me trouble-shoot this.

Had similar thing happen a couple of months ago. Turned key on and did not have any power. When checking the battery condition, I noticed a multi-wire connector block had disconnected from horn next to the battery(if that isn't the horn, then I just revealed/verified my ignorance. Reconnected the block and then everything was ok again. This was the first thing I looked at when losing power this time, but it remains properly connected.

Don't know if it has relevance, but for last several months I have heard buzzing noise through left speaker on dash after engine start. The buzzing sound would go up and down with engine revs. Could hear noise in speaker even with radio turned off. Really aggravating, but would be willing to hear it now as it would mean the car is started!

BTW, I am more than 100 miles from nearest Porsche dealer (under normal conditions I usually consider this to be a safe distance).

I do not have specialized test equipment

Any serious suggestions?

I am not sure that it would apply in this case from your description of how the problem originated (i.e., wires behind emergency flasher), but on all of the 986's and 996's, the electrical portion of the ignition switch is a frequent failure point, and it causes some otherwise inexplicable electrical gremlins.

Since the part is so inexpensive (about $10, and it's an Audi part, part number 4A0 905 849 B) and relatively easy DIY to replace, it may be worth a shot to eliminate that as a possible source of the problem.

Regards, Maurice.

Edited May 10, 2011 by nhobx

[violaGT3]

Glad to read it was figured out.

Edited May 11, 2011 by ViolaGT3