My first Porsche and chasing electrical issues

[NBTF]

Hi. Last week I bought a 1986 944 N/A all original stock from my father-in-law and everything worked except the retractable rear cover (minor) and the factory head unit was dying. Known issues I was told about were 1) needs a short shift kit (got it ordered) 2)random starting issues. The car will be a pleasure car and hoping to use it on road racing tracks with my father-in-law. I will get some pics poster later.

I have ordered the short shift kit and should arrive Monday. Bought an inexpensive headunit and door speakers for now so I could at least have some tunes while I sit in the car and work on it and post here. Radio works and everything else on the car also works.

Yesterday it acted up and did not want to start. Pulled and tested the DME relay (2 months old) and it checked ok. Created the DME jumper wires and tested the fuel pump, checked ok. Checked the speed and reference sensors and found one of the connectors was broken and cracked and after meter testing determined one of the lead internally is broken and randomly makes a connection. Got a new sensor on order.

Today I cleaned out the reference sensor plug of the broken housing bits and managed to electrical tape the connector just right and the car starts now. But the kicker now is the mirrors and windows do not want to work.

I have checked all fuses and they are good and correct values. Also pulled and inspected the relay and it appears to be good. I have removed the door speakers and no change. I thought maybe I had a connector backwards in the center console after installing the headunit. The sunroof button, central lock, and fade switch all work. the mirror switch appears to be on right, wires are facing the same way as the other switches. Did noticed an extra plug labeled '2', not sure what it would go to as there are no other switches to connect it to.

I think I have read every how-to in Clark's Garage twice now, lol.

So in summary:

1) What does the plug labeled 2 in the center console go to?
2)How would the windows and mirrors just stop working?
3)what troubleshooting can I do to try and fix the windows and mirrors?

Thanks in advance

[Will_S_944]

luckily I haven't had too many problems with my '44, except for the raking I got from 2 shops.... your extra plug should be for the rear wiper switch. the rear wiper harness terminates in the drivers side quarter panel area along side the sunroof motor.

My door mirrors and windows on the pass side had stopped working.. it was a dirty connection

[NBTF]

Thanks. Car came without the rear wiper so I know I don't have to worry about that plug. I have checked the driver side window switches and no power. Rechecked the fuses and they are still good.

[Shooter]

On the door switches-did you take them out and clean the contacts? Did you check with a meter or just flipping the switch? If a meter is showing no voltage at the switch you'll need to trace back to the fuse box. Was there power to the fuse box circuit? Cleaning the contacts on 25 year old cars is usually the first thing, almost all European cars have sub standard electrical systems and oxidation takes it toll. If they're pitted or corroded a pencil eraser can clean them up but its a short term fix, look for new ones, I think I bought them once from the Bird here. Also check the grounds.

[NBTF]

I have checked the driver door window switches and found no power. I pulled all fuses labeled window and mirror and all are visually and metered good. I am just finding it odd that windows and mirrors worked the night before.

I have tested the relay plug for G7 and there is power to the relay. I also ordered a spare just in case.

note: checked and had power to fuse 4.

[NBTF]

Ok, went back to Clark's Garage and reread the power window section and jumpered the relay plug (30 & 87) and the windows work now. Will wait for the spare relay to arrive.

Now to work on the power mirrors.

[NBTF]

Issue :
Neither mirror moves (also reverse lights not working, same fuse/circuit)


Mirror testing :
Fuse 28 has no power
Rechecked dash switch is connected after swapping out headunit

Removed dash mirror switch and metered 1/4, 2/6 and 1/3, 2/5. All contacts changed from OL to ~.4ohm. (I will go with the switch is good.)

[rhett]

The reversing lights, mirrors and the power window relays are all fed from the same circuit. By jumpering the power windows relay you have patched across the contacts and proved that the windows still work, however the drive to that relay is missing (the relay is probably OK). You have mentioned that fuse 28 has no power, so you should check relay G14, this is the common drive to all those circuits. It also drives the windshield wiper motor and the fresh air blower, so perhaps those are dead too, best check. If they are - then a faulty relay G14 is a big possibility. Sometimes corrosion on the relay pins is all it takes, pull it and check and clean it up if necessary.

Hope that helps.

[NBTF]

Now that you mention that the blower is not working, not sure about the wipers. I will check out G14 tomorrow. Gotta get ready for wife's b-day party tonight. Thanks for the help.

[petrolhead611]

European car electrical items corrode after 25 years! Oh dear that's terrible. How long does the average American house last because European ones last hundreds of years.

[NBTF]

Ok, so the window jumper band-aid fix is still working so I can at least tolerate driving it. Got several parts on order and waiting to arrive.

So far on order:
G14 relay
G7 relay
reference sensor (not looking forward to installing)
rebuilt starter
Throttle response cam
jack pad adapter
Haynes repair manual
K&N non-turbo intake
LED dome light bulb


Arrived:
Short shift kit (transmission end)
Dome light housing (broke it be stupid )


Small project working on while waiting for parts:
Dismantling an aux port USB charger and grafting into one of the blank acc switch covers. Almost done with it, just have to run power from a switching source. I will try and make a write up on it once I am done.

[NBTF]

G14 and G7 relays are in and everything (electrical) so far appears to be working now; windows, mirrors, wipers, blower, and reverse lights. Though fuse 28 still has no power.

Want to say thanks to rhett for guidance to G14.