17664 on 1996-2001 Audi A4 — Engine Coolant Temperature Circuit (G62): Open / Short to B+
1 vehicles · 1 makes · $30-$180 repair
Most Reported On
17664 is an OBD-II diagnostic trouble code meaning “Engine Coolant Temperature Circuit (G62): Open / Short to B+.” This VAG-specific fault code (OBD-II equivalent P1256) indicates the engine control module has detected an electrical fault in the Engine Coolant Temperature Sensor (G62) circuit — either an open circuit or a short to positive (B+). Because the ECM relies on coolant temperature to manage fuel delivery, ignition timing, and glow plug operation, a bad signal causes the engine to run on incorrect temperature data. Common symptoms include hard cold starts, high or irregular idle (1200–3000 RPM), poor warm-up acceleration, and erratic temperature gauge behavior. This code is most commonly reported on 1996-2001 Audi A4, with repair costs ranging from $30 to $180.
Common Causes
Typical Repair Cost
Based on 1 documented vehicle-specific issues. Actual cost depends on root cause and vehicle.
Diagnostic Tools
17664 does not use the standard P/B/C/U prefix. It may be a manufacturer-specific code, so verify that a scanner supports your exact year, model and module before buying.
FAQ
What does 17664 mean?
17664 stands for "Engine Coolant Temperature Circuit (G62): Open / Short to B+." This VAG-specific fault code (OBD-II equivalent P1256) indicates the engine control module has detected an electrical fault in the Engine Coolant Temperature Sensor (G62) circuit — either an open circuit or a short to positive (B+). Because the ECM relies on coolant temperature to manage fuel delivery, ignition timing, and glow plug operation, a bad signal causes the engine to run on incorrect temperature data. Common symptoms include hard cold starts, high or irregular idle (1200–3000 RPM), poor warm-up acceleration, and erratic temperature gauge behavior.
What are the most common causes of 17664?
The most common causes of 17664 are: Faulty Engine Coolant Temperature Sensor (G62) — original black sensors on 1995–2002 VWs are a known failure point, replaced by green units, Open or broken wiring between the sensor and the ECM, Short to positive (B+) in the sensor wiring, Corroded, loose, or damaged sensor connector, Wiring harness chafing or insulation damage near the sensor. The specific cause varies by vehicle.
How much does it cost to fix 17664?
Repair costs for 17664 range from $30 to $180, depending on the vehicle and root cause.
Which vehicles are affected by 17664?
Au7o has documented 17664 across 1 vehicle models from 1 manufacturers: Audi.
Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.