TS-09, Troubleshooting - Electrical (including Instruments)

Introduction

This troubleshooting guide is intented to help identify and repair specific electrical system problems. The following is a list of problem symptoms discussed in this guide:

On my late model 944, the wipers, blower motor, reverse lights, cooling fans, power windows, and power mirrors all quit working.

Possible Causes
Checks
Procedure
Relay X Bad. Remove Relay X from terminal board and install jumper in place of primary contacts to see if functions are restored. N/A

Dash Lights are too dim.

Possible Causes
Checks
Procedure
Flaking of instrument bezel reflective coating, burned out bulbs, or bulb wattage too low. Refer to Instrument Panel Light procedure. ELECT-08

Rear Defroster Doesn't Work

Possible Causes
Checks
Procedure
Damaged lug, damaged grid, loss of power. Refer to Rear Hatch Defroster Troubleshooting and Repair procedure. ELECT-05

Battery goes dead after a short period of time.

Possible Causes
Checks
Procedure
Possible ground on electrical system. Use the Excessive Battery Discharge Rate procedure to try and isolate the problem. ELECT-26

Fuse #11 Blown (1985 through 1989 944, 944S, 944S2, 944 Turbo)

Possible Causes
Checks
Procedure
Ground in glove compartment light wiring. The red wire located on the glove compartment light of 1985 through 1989 944 series cars could rub against the metal brace above the glove compartment causing fuse # 11 to blow. This could be an intermittent condition. To repair this, bend the red wire down away from the brace or switch the red and brown wire positions on the light assembly. This problem was addressed by TSB-98902.

One of my instrument panel gauges is not working properly.

Possible Causes
Checks
Procedure
Faulty gauge, sensor, or wiring. Troubleshoot using Sensors and Gauges procedure. ELECT-19

My turn signal blinks faster on one side than the other.

Possible Causes
Checks
Procedure
Dirty bulb socket or bulb contacts. A rapidly blinking turn signal on one side is the result of a dirty bulb holder or dirty bulb contacts. Remove the turn signal bulbs on the side that is blinking rapidly and clean the bulb sockets with a wire brush. Clean the contacts on the bulb with emery cloth or other mildly abrasive material. Coat the bulb contacts with a light coating of dielectric grease and reinstall.

My turn signal light comes on but does not blink.

Possible Causes
Checks
Procedure
Bad bulb or flasher relay. If your turn signal light comes on but does not blink on one side, you most likely have a bad bulb on that side. Remove the bulbs and determine which bulb is bad by looking for a broken filament in the bulbs. If the turn signal lights come on but, do not blink on either side, your flasher relay is most likely bad and should be replaced. N/A

Clark's Garage 1998