Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
1990 Volkswagen Cabriolet Base, AutomaticFACTORY OEM SERVICE PROCEDURE
Power Circuits
- Turn ignition off. Disconnect ECU connector. Using a voltmeter, turn ignition on and check for battery voltage between ECU connector terminals No. 13 (negative) and No. 14 (positive). See WIRING DIAGRAMS for terminal identification and wire colors. If battery voltage is not present, repair wiring as required.
- Check terminals No. 13 (negative) and No. 1 (positive) for battery voltage. If battery voltage is not present, check fuse No. 18 on fuse block. If fuse is okay, check wiring from ECU connector to fuse box for open.
Factory Service Tools
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
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