Cooling & temperature fault codes
138 VAG and OBD-II codes covering cooling and temperature, each with what it means in plain English and how urgent it is.
| Code | Definition | Severity |
|---|---|---|
00256 | Refrigerant Pressure/Temperature Sensor (G395): Electrical Fault / Implausible Signal | Investigate soon |
00300 | Transmission Fluid Temperature Sensor (G93) - Implausible/Out of Range | Investigate soon |
00489 | Outlet / Vent Temperature Sensor, Rear Left (G405): Electrical Fault | Investigate soon |
00522 | Engine Coolant Temperature Sensor (G62) - Implausible Signal | Do not keep driving |
00534 | Engine Oil Temperature Sensor (G8) - Malfunction | Investigate soon |
00667 | Outside (Ambient) Air Temperature Signal - Malfunction | Investigate soon |
00779 | Outside Air Temperature Sensor (G17): Open or Short to Plus/Ground | Investigate soon |
01028 | Coolant (Radiator) Fan Blower Motor Relay - Malfunction | Investigate soon |
01039 | Engine Coolant Temperature Sensor (G2): Electrical Fault / Implausible Signal | Do not keep driving |
01183 | Catalytic Converter - Overtemperature / Malfunction | Investigate soon |
01193 | Engine Coolant (Auxiliary Heater) Relay 1, Low Output - Malfunction | Investigate soon |
01194 | Engine Coolant (Auxiliary Heater) Relay 2, High Output - Malfunction | Investigate soon |
01204 | Engine Coolant Temperature Sensor - Malfunction | Do not keep driving |
17866 | Exhaust gas temperature sensor 2 (bank 2, G236): short to ground | Investigate soon |
17869 | Exhaust gas temperature control, bank 1: Range/Performance (implausible signal) [DE: Abgastemperaturregelung Zylinderreihe 1: unplausibles Signal] | Investigate soon |
B1085 | Footwell Vent (Outlet) Temperature Sensor — HVAC footwell duct temp sensor, short-to-ground / open / short-to-B+ / implausible | Investigate soon |
B1086 | Center Vent (Outlet) Temperature Sensor — center-dash outlet temp sensor, open/short/implausible | Investigate soon |
B1087 | Left (Driver-Side) Vent (Outlet) Temperature Sensor — outlet duct temp sensor, open/short/implausible | Investigate soon |
B1094 | Left Temperature Flap Position Sensor / Feedback Potentiometer (G220) — short-to-ground / open / short-to-B+ | Investigate soon |
B1095 | Right Temperature Flap Position Sensor / Feedback Potentiometer (G221) — short-to-ground / open / short-to-B+ | Investigate soon |
B1096 | Xenon/Ballast Overtemperature or Overvoltage; Left Headlight | Investigate soon |
B1097 | Xenon/Ballast Overtemperature or Overvoltage; Right Headlight | Investigate soon |
P0070 | Ambient Air Temperature Sensor Circuit A | Investigate soon |
P0071 | Ambient Air Temperature Sensor Circuit A Range/Performance | Investigate soon |
P0072 | Ambient Air Temperature Sensor Circuit A Low | Investigate soon |
P0073 | Ambient Air Temperature Sensor Circuit A High | Investigate soon |
P0074 | Ambient Air Temperature Sensor Circuit A Intermittent/Erratic | Investigate soon |
P00B1 | Radiator Coolant Temperature Sensor Circuit | Do not keep driving |
P00B2 | Radiator Coolant Temperature Sensor Circuit Range/Performance | Do not keep driving |
P00B3 | Radiator Coolant Temperature Sensor Circuit Low | Do not keep driving |
P00B4 | Radiator Coolant Temperature Sensor Circuit High | Do not keep driving |
P00B5 | Radiator Coolant Temperature Sensor Circuit Intermittent/Erratic | Do not keep driving |
P00B6 | Radiator Coolant Temperature/Engine Coolant Temperature Correlation | Do not keep driving |
P00B7 | Engine Coolant Flow Low/Performance | Investigate soon |
P0115 | Engine Coolant Temperature Sensor 1 Circuit | Do not keep driving |
P0116 | Engine Coolant Temperature Sensor 1 Circuit Range/Performance | Do not keep driving |
P0117 | Engine Coolant Temperature Sensor 1 Circuit Low | Do not keep driving |
P0118 | Engine Coolant Temperature Sensor 1 Circuit High | Do not keep driving |
P0119 | Engine Coolant Temperature Sensor 1 Circuit Intermittent/Erratic | Do not keep driving |
P011A | Engine Coolant Temperature Sensor 1/2 Correlation | Do not keep driving |
P0126 | Insufficient Coolant Temperature for Stable Operation | Do not keep driving |
P0128 | Coolant Thermostat (Coolant Temperature Below Thermostat Regulating Temperature) | Do not keep driving |
P0195 | Engine Oil Temperature Sensor A Circuit | Investigate soon |
P0196 | Engine Oil Temperature Sensor A Range/Performance | Investigate soon |
P0197 | Engine Oil Temperature Sensor A Circuit Low | Investigate soon |
P0198 | Engine Oil Temperature Sensor A Circuit High | Investigate soon |
P0199 | Engine Oil Temperature Sensor A Circuit Intermittent/Erratic | Investigate soon |
P0218 | Transmission Fluid Temperature Sensor A Over Temperature Condition | Investigate soon |
P0298 | Engine Oil Over Temperature | Investigate soon |
P0480 | Cooling Fan 1 Control Circuit Malfunction | Investigate soon |
P0481 | Cooling Fan 2 Control Circuit Malfunction | Investigate soon |
P0482 | Cooling Fan 3 Control Circuit Malfunction | Investigate soon |
P0484 | Cooling Fan Circuit Over Current | Investigate soon |
P050C | Cold Start Engine Coolant Temperature Performance | Do not keep driving |
P050E | Cold Start Engine Exhaust Temperature Too Low | Investigate soon |
P0514 | Battery Temperature Sensor Circuit Range/Performance | Investigate soon |
P0515 | Battery Temperature Sensor Circuit | Investigate soon |
P0516 | Battery Temperature Sensor Circuit Low | Investigate soon |
P0517 | Battery Temperature Sensor Circuit High | Investigate soon |
P0544 | Exhaust Gas Temperature Sensor Circuit Bank 1 Sensor 1 | Investigate soon |
P0545 | Exhaust Gas Temperature Sensor Circuit Low Bank 1 Sensor 1 | Investigate soon |
P0546 | Exhaust Gas Temperature Sensor Circuit High Bank 1 Sensor 1 | Investigate soon |
P0547 | Exhaust Gas Temperature Sensor Circuit Bank 2 Sensor 1 | Investigate soon |
P0548 | Exhaust Gas Temperature Sensor Circuit Low Bank 2 Sensor 1 | Investigate soon |
P0549 | Exhaust Gas Temperature Sensor Circuit High Bank 2 Sensor 1 | Investigate soon |
P0597 | Thermostat Heater Control Circuit/Open | Investigate soon |
P0598 | Thermostat Heater Control Circuit Low | Investigate soon |
P0599 | Thermostat Heater Control Circuit High | Investigate soon |
P060F | Internal Control Module Coolant Temperature Performance | Do not keep driving |
P0634 | PCM / ECM / TCM Internal Temperature Too High | Investigate soon |
P063F | Auto Configuration Engine Coolant Temperature Input Not Present | Do not keep driving |
P0666 | PCM / ECM / TCM Internal Temperature Sensor Circuit | Investigate soon |
P0667 | PCM / ECM / TCM Internal Temperature Sensor Range/Performance | Investigate soon |
P0668 | PCM / ECM / TCM Internal Temperature Sensor Circuit Low | Investigate soon |
P0669 | PCM / ECM / TCM Internal Temperature Sensor Circuit High | Investigate soon |
P06AA | Control Module Internal Temperature B Too High | Investigate soon |
P0710 | Transmission Fluid Temperature Sensor A Circuit | Investigate soon |
P0711 | Transmission Fluid Temperature Sensor A Circuit Range/Performance | Investigate soon |
P0712 | Transmission Fluid Temperature Sensor A Circuit Low | Investigate soon |
P0713 | Transmission Fluid Temperature Sensor A Circuit High | Investigate soon |
P0714 | Transmission Fluid Temperature Sensor A Circuit Intermittent | Investigate soon |
P0937 | Hydraulic Oil Temperature Sensor Circuit | Investigate soon |
P0938 | Hydraulic Oil Temperature Sensor Range/Performance | Investigate soon |
P0939 | Hydraulic Oil Temperature Sensor Circuit Low | Investigate soon |
P0940 | Hydraulic Oil Temperature Sensor Circuit High | Investigate soon |
P0941 | Hydraulic Oil Temperature Sensor Circuit Intermittent | Investigate soon |
P0A7E | Hybrid/EV Battery Pack A Over Temperature | Investigate soon |
P1255 | Engine Coolant Temperature Sensor (G62) Circuit: Short to Ground | Do not keep driving |
P1256 | Engine Coolant Temperature Sensor (G62) Circuit: Open/Short to B+ | Do not keep driving |
P1257 | Engine Coolant System Valve: Open | Investigate soon |
P1258 | Engine Coolant System Valve: Short to B+ | Investigate soon |
P1259 | Engine Coolant System Valve: Short to Ground | Investigate soon |
P1296 | Cooling System Malfunction | Investigate soon |
P1620 | Engine Coolant Temperature Sensor (G62) - Open / Short to B+ | Do not keep driving |
P1621 | Engine Coolant Temperature Sensor (G62) - Short to Ground | Do not keep driving |
P1622 | Engine Coolant Temperature Sensor (G62) - Range/Performance (Implausible Signal) | Do not keep driving |
P2031 | Exhaust Gas Temperature Sensor Circuit Bank 1 Sensor 2 | Investigate soon |
P2032 | Exhaust Gas Temperature Sensor Circuit Low Bank 1 Sensor 2 | Investigate soon |
P2033 | Exhaust Gas Temperature Sensor Circuit High Bank 1 Sensor 2 | Investigate soon |
P2034 | Exhaust Gas Temperature Sensor Circuit Bank 2 Sensor 2 | Investigate soon |
P2035 | Exhaust Gas Temperature Sensor Circuit Low Bank 2 Sensor 2 | Investigate soon |
P2036 | Exhaust Gas Temperature Sensor Circuit High Bank 2 Sensor 2 | Investigate soon |
P2080 | Exhaust Gas Temperature Sensor Circuit Range/Performance Bank 1 Sensor 1 | Investigate soon |
P2081 | Exhaust Gas Temperature Sensor Circuit Intermittent Bank 1 Sensor 1 | Investigate soon |
P2082 | Exhaust Gas Temperature Sensor Circuit Range/Performance Bank 2 Sensor 1 | Investigate soon |
P2083 | Exhaust Gas Temperature Sensor Circuit Intermittent Bank 2 Sensor 1 | Investigate soon |
P2084 | Exhaust Gas Temperature Sensor Circuit Range/Performance Bank 1 Sensor 2 | Investigate soon |
P2085 | Exhaust Gas Temperature Sensor Circuit Intermittent Bank 1 Sensor 2 | Investigate soon |
P2086 | Exhaust Gas Temperature Sensor Circuit Range/Performance Bank 2 Sensor 2 | Investigate soon |
P2087 | Exhaust Gas Temperature Sensor Circuit Intermittent Bank 2 Sensor 2 | Investigate soon |
P2181 | Cooling System Performance | Investigate soon |
P2182 | Engine Coolant Temperature Sensor 2 Circuit | Do not keep driving |
P2183 | Engine Coolant Temperature Sensor 2 Circuit Range/Performance | Do not keep driving |
P2184 | Engine Coolant Temperature Sensor 2 Circuit Low | Do not keep driving |
P2185 | Engine Coolant Temperature Sensor 2 Circuit High | Do not keep driving |
P2186 | Engine Coolant Temperature Sensor 2 Circuit Intermittent/Erratic | Do not keep driving |
P2478 | Exhaust Gas Temperature Out of Range Bank 1 Sensor 1 | Investigate soon |
P2479 | Exhaust Gas Temperature Out of Range Bank 1 Sensor 2 | Investigate soon |
P247A | Exhaust Gas Temperature Out of Range Bank 1 Sensor 3 | Investigate soon |
P247B | Exhaust Gas Temperature Out of Range Bank 1 Sensor 4 | Investigate soon |
P247C | Exhaust Gas Temperature Out of Range Bank 2 Sensor 1 | Investigate soon |
P247D | Exhaust Gas Temperature Out of Range Bank 2 Sensor 2 | Investigate soon |
P247E | Exhaust Gas Temperature Out of Range Bank 2 Sensor 3 | Investigate soon |
P247F | Exhaust Gas Temperature Out of Range Bank 2 Sensor 4 | Investigate soon |
P2556 | Engine Coolant Level Sensor/Switch Circuit | Investigate soon |
P2558 | Engine Coolant Level Sensor/Switch Circuit Low | Investigate soon |
P2560 | Engine Coolant Level Low | Investigate soon |
P2600 | Coolant Pump A Control Circuit/Open | Investigate soon |
P2602 | Coolant Pump A Control Circuit Low | Investigate soon |
P2603 | Coolant Pump A Control Circuit High | Investigate soon |
P261A | Coolant Pump B Control Circuit/Open | Investigate soon |
P261C | Coolant Pump B Control Circuit Low | Investigate soon |
P261D | Coolant Pump B Control Circuit High | Investigate soon |
P2740 | Transmission Fluid Temperature Sensor B Circuit | Investigate soon |
P2741 | Transmission Fluid Temperature Sensor B Circuit Range/Performance | Investigate soon |
P2743 | Transmission Fluid Temperature Sensor B Circuit High | Investigate soon |
P2744 | Transmission Fluid Temperature Sensor B Circuit Intermittent | Investigate soon |
U0116 | Lost Communication With Coolant Temperature Control Module | Do not keep driving |
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