Troubleshooting - Electrical (Including Instruments)
Symptom-driven guide to diagnosing electrical problems on the Porsche 944, including multiple system failures, dim dash lights, dead battery, blown fuses, gauge problems, and turn signal faults.
Vanskelighetsgrad: Middels3 min lesingGjelder for: 944 · 944S · 944S2 · 944 Turbo
Denne prosedyren er ikke oversatt ennå og vises på engelsk.
Introduction
This troubleshooting guide is intended to help identify and repair specific electrical system problems. Symptoms covered:
- On late-model 944, the wipers, blower motor, reverse lights, cooling fans, power windows, and power mirrors all quit working
- Dash lights are too dim
- Rear defroster does not work
- Battery goes dead after a short period of time
- Fuse #11 Blown (1985 through 1989 944, 944S, 944S2, 944 Turbo)
- One of the instrument panel gauges is not working properly
- Turn signal blinks faster on one side than the other
- Turn signal light comes on but does not blink
Wipers, Blower Motor, Reverse Lights, Cooling Fans, Power Windows, and Power Mirrors All Quit Working (Late-Model 944)
| Possible Cause | Checks | Procedure |
|---|---|---|
| Relay X bad | Remove Relay X from the terminal board and install a jumper across the primary contacts to see if the affected functions are restored. | N/A |
Dash Lights Are Too Dim
| Possible Cause | Checks | Procedure |
|---|---|---|
| Flaking of instrument bezel reflective coating, burned-out bulbs, or bulb wattage too low | Refer to the Instrument Panel Light procedure. | ELECT-08 |
Rear Defroster Doesn't Work
| Possible Cause | Checks | Procedure |
|---|---|---|
| Damaged lug, damaged grid, or loss of power | Refer to the Rear Hatch Defroster Troubleshooting and Repair procedure. | ELECT-05 |
Battery Goes Dead After a Short Period of Time
| Possible Cause | Checks | Procedure |
|---|---|---|
| Excessive current draw (possible ground fault in the electrical system) | Use the Excessive Battery Discharge Rate procedure to isolate the problem. | ELECT-26 |
Fuse #11 Blown (1985 Through 1989 944, 944S, 944S2, 944 Turbo)
| Possible Cause | Checks | Procedure |
|---|---|---|
| Ground in glove compartment light wiring | The red wire on the glove compartment light of 1985–1989 944 series cars can rub against the metal brace above the glove compartment, causing fuse #11 to blow intermittently. Bend the red wire down away from the brace, or swap the red and brown wire positions on the light assembly. This problem was addressed by TSB-98902. | N/A |
One of the Instrument Panel Gauges Is Not Working Properly
| Possible Cause | Checks | Procedure |
|---|---|---|
| Faulty gauge, sensor, or wiring | Troubleshoot using the Sensors and Gauges procedure. | ELECT-19 |
Turn Signal Blinks Faster on One Side Than the Other
| Possible Cause | Checks | Procedure |
|---|---|---|
| Dirty bulb socket or bulb contacts | A rapidly blinking turn signal on one side is the result of dirty bulb socket contacts. Remove the turn signal bulbs on the fast-blinking side and clean the sockets with a wire brush. Clean the contacts on the bulbs with emery cloth or another mildly abrasive material. Coat the bulb contacts with a light coating of dielectric grease and reinstall. | N/A |
Turn Signal Light Comes On But Does Not Blink
| Possible Cause | Checks | Procedure |
|---|---|---|
| Bad bulb or flasher relay | If only one side fails to blink, the most likely cause is a bad bulb on that side — remove the bulbs and look for a broken filament. If neither side blinks, the flasher relay is most likely bad and should be replaced. | N/A |
Emneord:electricalinstrumentsrelayfusebatteryturn signalgaugesdashboard