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.
1994 Audi 90 CS QuattroFACTORY OEM SERVICE PROCEDURE
Using Malfunction Indicator Light (MIL)
- Turn ignition on. Remove cover from fuse/relay block under left side of instrument panel. See Figure or Figure . Connect Jumper Cable (357 971 514E) to Data Link Connectors (DLC). Black end of jumper cable attaches to Black DLC; White end of cable attaches to White DLC; Blue DLC is not used.
- Leave jumper cables attached for 5 seconds, until MIL begins to blink. Remove jumper cable. Allow on-board diagnostic code retrieval procedure to run until Code 4444 (no faults indicated) or Code 0000 (end of output) appears. To end code retrieval procedure, reconnect jumper cable to DLC or turn ignition off.
NOTE:
Retrieve codes with engine running if possible. Before retrieving codes, initiate output DTM, perform engine basic setting and read measuring block values. Before testing system performance or replacing components, check for poor connection at ground wires attached to intake manifold, right engine mount and battery negative terminal.
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.