sh944s

I am new the the 964 world but have been a Porsche 944 guy since 1990. I recently purchased a 1990 C2 which I am really enjoying. I replaced the front fans (thanks to helpful threads on Rennlist!) and now the air bag light is constantly on.

I had this happen once before when I removed the seats. The only thing that seems to be the same in both instances is I turned the key to the on position when connectors were disconnected, in the case of the seats it was the seat belt and power seat connections, in the case of the fans it was a connection on the right hand blower housing.

Well, I took the car back to the place where they reset the first fault and they told me they were unable to reset the light due to a code indicating a left front crash sensor malfuction.

Now I am inclined to think that this crash sensor didn't just decided to crap out while sitting in the garage. Can anyone offer any advice on troubleshooting? I have ordered the T-OBD tool and have read about the clock circuit card issues. Would I be best advised remove the clock, do the suggested repairs and try to reset or just drop the baby off, open the wallet and let the mechanic start replaceing sensors (only to find out later that it was the clock).

Any help is appreciated

Here is the car.

jody stowitts

Go to dealer ask for reset with Bosch hammer & check on increased resistance @ or in one of the crash sensors first. THEN do your other diagnostic thing(s) if ?? Cheers!

jody stowitts

Noticed you've got side indicators. Did your car emanate from Britain? Possible rust-corrosion from fog-marine air in wet climate (how many years) has increased the resistance @ ground? Again, Cheers!

Makmov

I got a different error for the airbag with it was the clock. I am trying to remember, but it was wasn't a sensor error. The way I understand it, if you disconnect a sensor where you indicated with the batt hooked up it will write a permenent error into the control unit in which case you need someone who can tap that and replace it with good hexdecimal code or replace the control unit.

That was a mistake to disconnect the sensor while powered up. I always disconnect the batt for the fans and ALWAYS check and recheck the connectors before hooking up the batt and turning anything on.

The sensor itself is a pretty bullet proof simple device that should last forever.

Now the connection can cause problems, I have read, but after having them apart myself I can't imagine how many years underwater it would take for a bad connection to show up.

dfinnegan

Try and disconnect the sensor wire in the front boot up near the firewall. Clean the contacts, and reconnect.

It's a bit fiddly, to say the least, but you should be able to get to the wire.

I've had this same error and cleaning the contact did the trick.

993James993

I've read that you should disconnect the battery and let it set before attempting this or you may accidentally deploy the airbag. I've been afraid to do this for that reason.

I have the scan tool device and get the same code. I cleared the code and the warning light went out for a month or so but returned. Now when I clear the code it returns right away.

I've decided to take the car to the local dealership to sort out an alarm issue and will report what they find with the crash sensor.

sh944s

Thanks for all the suggestions. Just to clarify, i did not disconnect the crash sensors at any time during my replacement of the fans.

I am going to disconnect the battery and clean the contacts to the sensor. I have a scan tool on order which won't be in until August so I will have to wait to see if cleaning connections takes care of the issue.

BTW the car is a Euro model imported to the US in 2000. I'm not sure where it was originally sold but I found a bunch of Lira under the seat. Italy perhaps?

Makmov

You pretty much have to disconnect the crash sensor plug to do the blower motors as they are routed through the fire wall which must be removed to get to the housings.

sh944s

Makmov...thanks for correcting me. I didn't realize the two connectors that run through the firewall lead to the crash sensors.

I should inspect the plugs to be sure they are fully engaged.

berni29

Hi

I have the "Front sensor left contact resistance" error code on my 1994 993 at the moment. My car uses the same crash sensor as the 964 and I access it through the 964 airbag menu. I am really hoping that wiggling the wires or cleaning the contacts will fix the fault. I have not had my head up under the glovebox (that is the position of the unit on the 993 apparently) to see what the unit looks like yet.

Apparently the crash sensors can fail while just sitting doing nothing. I hope not as it is not a straightforward fix. The unit is paired to the car via the VIN.

All the best

Berni

sh944s

I got in the trunk this afternoon and I fogot to reconnect the senosor plug when I was putting the firewall back in. As is often the case, these faults are self induced.

Thanks again to everone for the help. Now to get the code reset.

sschultze09

sh944s I am dealing with the same crash sensor fault code that you are. Are the sensors and connections located in the trunk or under the wheel wells?
I can't seem to locate them in PET.
Thanks,

Vincent C.

the sensors are in the trunk....vinnie

sh944s

Sensors are located just in front of the fuel tank on each frame rail. They are little black boxes. If you follow the wires you will find the connectors attached to the firewall. The left is under the fuel filler hose and the right is just in front of the fuse panel. They are round 3 pin connectors.

Hope this helps.

sschultze09

Thanks again, Vinnie
General location?