Troubleshooting Troubleshooting – Electrical (including Instruments) – 2.5L NA Estimated reading: 3 minutes Contributors Overview This guide provides troubleshooting steps for electrical and instrument-related issues specific to the Porsche 944 3.0L S2 (1989–1991). It addresses common problems such as wiper failure, dim dashboard lights, and blown fuses, tailored for the late-model 944 S2 with alloy control arms. Proper diagnosis and repair are critical to maintaining the vehicle’s electrical system functionality and ensuring safe operation. Troubleshooting – Electrical (including Instruments) The following table lists common electrical and instrument issues, their possible causes, checks, and procedures for the Porsche 944 3.0L S2. Symptom Possible Causes Checks Procedure Wipers, blower motor, reverse lights, cooling fans, power windows, and power mirrors all quit working 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 Flaking of instrument bezel reflective coating, burned out bulbs, or bulb wattage too low Refer to Instrument Panel Light procedure. Instrument Panel Light Rear defroster does not work Damaged lug, damaged grid, loss of power Refer to Rear Hatch Defroster Troubleshooting and Repair procedure. Rear Hatch Defroster Troubleshooting and Repair Battery goes dead after a short period of time Possible ground on electrical system Use the Excessive Battery Discharge Rate procedure to try and isolate the problem. Excessive Battery Discharge Rate Fuse #11 Blown Ground in glove compartment light wiring The red wire on the glove compartment light could rub against the metal brace above the glove compartment, causing fuse #11 to blow. This could be intermittent. Bend the red wire down away from the brace or switch the red and brown wire positions on the light assembly. Refer to TSB-98902. Instrument panel gauge not working properly Faulty gauge, sensor, or wiring Troubleshoot using Sensors and Gauges procedure. Sensors and Gauges Turn signal blinks faster on one side Dirty bulb socket or bulb contacts A rapidly blinking turn signal is due to a dirty bulb holder or contacts. Remove the turn signal bulbs on the affected side and clean the bulb sockets with a wire brush. Clean bulb contacts with emery cloth or mildly abrasive material. Coat contacts with dielectric grease and reinstall. Turn signal light comes on but does not blink Bad bulb or flasher relay If the turn signal light comes on but does not blink on one side, check for a bad bulb. If neither side blinks, the flasher relay is likely bad. Remove bulbs and inspect for broken filaments. Replace bad bulbs. If neither side blinks, replace the flasher relay. Sources Clark’s Garage Pelican Parts Porsche 944 Workshop Manuals YouTube Tagged:Electrical Troubleshooting – Electrical (including Instruments) – 2.5L NA - PreviousTroubleshooting – Brakes – 2.5L NANext - Troubleshooting – Electrical (including Instruments) – 2.5L NATroubleshooting – Engine – 2.5L NA
