Fixes
Every trouble code page ends in a list of what might be wrong. This is that list turned around: the repairs themselves, ordered by how many faults each one is the first thing to check on.
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120 fixes
- Damaged data bus wiring moderate first check on 205 codes
- Low or degraded transmission fluid moderate first check on 204 codes
- Damaged cell voltage sense harness specialist first check on 166 codes
- Debris in the transmission fluid specialist first check on 147 codes
- Faulty pressure control solenoid specialist first check on 147 codes
- Worn valve body specialist first check on 133 codes
- Corroded transmission connector moderate first check on 117 codes
- Damaged wiring under the front seats specialist first check on 106 codes
- Faulty oxygen sensor moderate first check on 97 codes
- Damaged transmission wiring harness moderate first check on 87 codes
- Faulty power inverter specialist first check on 83 codes
- Poor wiring splice in an aftermarket installation moderate first check on 82 codes
- Failed power or earth supply to the module moderate first check on 81 codes
- Faulty battery pack sensor module specialist first check on 79 codes
- Faulty battery temperature sensor specialist first check on 79 codes
- Water ingress into the module connector moderate first check on 78 codes
- Failed fuel injector moderate first check on 74 codes
- Module not coded to the vehicle specialist first check on 73 codes
- Faulty cylinder deactivation solenoid specialist first check on 72 codes
- Faulty on-board charger specialist first check on 69 codes
- Faulty ignition coil easy first check on 68 codes
- Open circuit in the airbag deployment loop specialist first check on 65 codes
- Faulty DC-DC converter specialist first check on 62 codes
- Failed shift solenoid moderate first check on 61 codes
- Broken wire in the door harness boot moderate first check on 59 codes
- Clogged fuel injectors moderate first check on 58 codes
- Failed cell balancing circuit specialist first check on 58 codes
- Disconnected sensor connector easy first check on 55 codes
- Broken wire in control circuit moderate first check on 54 codes
- Open circuit in solenoid wiring moderate first check on 53 codes
- Incorrect module configuration after replacement specialist first check on 52 codes
- Low or dirty engine oil easy first check on 52 codes
- Water ingress into module moderate first check on 49 codes
- Second hand module locked to another vehicle specialist first check on 46 codes
- Worn or fouled spark plugs easy first check on 46 codes
- Leaking fuel injector moderate first check on 45 codes
- Open or shorted solenoid winding easy first check on 45 codes
- Signal wire shorted to ground moderate first check on 45 codes
- Faulty auxiliary transmission fluid pump specialist first check on 44 codes
- Sensor drifted out of calibration moderate first check on 44 codes
- Weak or failed cell group in the battery pack specialist first check on 44 codes
- Software updated on one module only specialist first check on 41 codes
- Faulty inverter coolant pump specialist first check on 39 codes
- Open circuit in injector wiring moderate first check on 39 codes
- Road damage to underfloor wiring moderate first check on 39 codes
- Blocked door drain letting water into the module easy first check on 38 codes
- Faulty battery pack coolant control valve specialist first check on 38 codes
- Faulty motor position sensor specialist first check on 38 codes
- Heat damage to sensor or wiring moderate first check on 37 codes
- Damaged high voltage phase cable or terminal specialist first check on 36 codes
- Exhaust leak before the sensor moderate first check on 35 codes
- Faulty electric air conditioning compressor specialist first check on 35 codes
- Faulty motor temperature sensor specialist first check on 34 codes
- Faulty seat belt pretensioner specialist first check on 34 codes
- Failed oxygen sensor heater element easy first check on 32 codes
- Faulty shift fork position sensor specialist first check on 32 codes
- Damaged charging inlet or pins moderate first check on 31 codes
- Faulty airbag module or initiator specialist first check on 31 codes
- Faulty NOx sensor moderate first check on 31 codes
- Hybrid battery pack deterioration specialist first check on 31 codes
- Metal debris on the sensor tip specialist first check on 30 codes
- Faulty battery contactor specialist first check on 29 codes
- Faulty clutch actuator specialist first check on 29 codes
- Faulty hybrid battery cooling fan moderate first check on 29 codes
- Faulty motor current sensor specialist first check on 29 codes
- Blocked deactivation solenoid oil screen specialist first check on 28 codes
- Fluid tracking into the transmission connector moderate first check on 28 codes
- Poor module ground connection moderate first check on 28 codes
- Failed control module specialist first check on 27 codes
- Faulty inverter coolant temperature sensor moderate first check on 27 codes
- Worn or leaking fuel injectors specialist first check on 27 codes
- Failed glow plug moderate first check on 26 codes
- Low inverter coolant level easy first check on 26 codes
- Disconnected or leaking vacuum hose easy first check on 25 codes
- Faulty accelerator pedal position sensor easy first check on 25 codes
- Faulty aftermarket alarm or immobiliser installation moderate first check on 25 codes
- Open circuit in actuator wiring specialist first check on 25 codes
- Aftermarket head unit fitted in place of the original moderate first check on 24 codes
- Damaged wiring harness near exhaust heat moderate first check on 24 codes
- Failed cylinder deactivation lifter specialist first check on 24 codes
- Faulty transmission range sensor specialist first check on 24 codes
- Faulty camshaft position sensor moderate first check on 23 codes
- Faulty receiving module input specialist first check on 23 codes
- Chafed harness against engine or bracket moderate first check on 22 codes
- Faulty exhaust gas temperature sensor moderate first check on 22 codes
- Faulty occupant classification module specialist first check on 22 codes
- Injector fitted without entering its calibration code specialist first check on 22 codes
- Vacuum leak in intake manifold or hoses moderate first check on 22 codes
- Actuator not calibrated after repair moderate first check on 21 codes
- Air trapped in the inverter cooling circuit moderate first check on 21 codes
- Blocked hybrid battery cooling fan intake easy first check on 21 codes
- Carbon deposits in the throttle body easy first check on 21 codes
- Faulty crankshaft position sensor moderate first check on 21 codes
- Faulty cruise control switch moderate first check on 21 codes
- Faulty engine coolant temperature sensor easy first check on 21 codes
- Faulty gear shift actuator specialist first check on 21 codes
- Faulty reductant temperature sensor moderate first check on 21 codes
- Impact sensor disturbed during body repair moderate first check on 21 codes
- Worn transmission friction element specialist first check on 21 codes
- Battery disconnected or module reprogrammed easy first check on 20 codes
- Faulty alternative fuel hydraulic pump specialist first check on 20 codes
- Clogged camshaft solenoid oil screen easy first check on 19 codes
- Faulty alternator moderate first check on 19 codes
- Faulty transmission fluid temperature sensor specialist first check on 19 codes
- Low hydraulic pressure in the clutch actuator specialist first check on 19 codes
- Physical damage from road debris moderate first check on 19 codes
- Corroded accelerator pedal connector easy first check on 18 codes
- Faulty alternative fuel vaporizer specialist first check on 18 codes
- Faulty transmission fluid pressure sensor moderate first check on 18 codes
- Open sensor ground circuit moderate first check on 18 codes
- Restricted fuel filter easy first check on 18 codes
- Short circuit in a transmission solenoid moderate first check on 18 codes
- Failed boost control solenoid moderate first check on 17 codes
- Failed camshaft oil control solenoid easy first check on 17 codes
- Fault in the external charging equipment easy first check on 17 codes
- Faulty ABS hydraulic modulator specialist first check on 17 codes
- Faulty alternative fuel tank shutoff valve specialist first check on 17 codes
- Faulty ignition switch moderate first check on 17 codes
- Faulty reductant injector specialist first check on 17 codes
- Faulty wheel speed sensor moderate first check on 17 codes
Before anything else
These turn up across every system rather than pointing at one, which makes them the commonest thing genuinely wrong with a car and the least informative about your fault in particular. Listed apart so they do not take the top of the ranking.
- Corroded or loose connector
- Open circuit in sensor wiring
- Damaged wiring harness
- Wiring shorted to ground
- Wiring shorted to voltage
- Open circuit in control wiring
- Water ingress into connector
- Intermittent wiring fault
- Blown fuse or failed supply
- Corroded earth connection
- Low system voltage
- Failed sensor reference voltage supply
- Control module driver failure
Information, not instruction
CarGeek is a reference, not a service manual. Its pages are written from public sources and from what other people have found, never from a manufacturer's own service information, so they can be wrong or incomplete for your particular vehicle. Some of what they describe carries real risk: high voltage, fuel under pressure, stored energy, hot and moving parts.
Have anything you intend to act on checked by a trained person against the manufacturer's own procedure for your vehicle. Nothing here replaces that procedure.