Control module and its circuits
The control unit itself, its power supply and circuits. These codes often arrive in a bunch after a flat battery or someone else's work on the wiring.
21 codes in this section, 21 with a guide
What it usually turns out to be
- A whole bunch of codes after a flat battery is usually a consequence, not a cause.
- Power and earths first, talk of replacing the unit last.
- If the code appeared after someone fitted an alarm, look for a splice in the wiring.
P0600Internal control module communication errorguideP0601Internal control module memory errorguideP0603Internal control module keep alive memory errorguideP0605Internal control module ROM errorguideP0606Internal control module processor errorguideP0620Generator control circuit — malfunctionguideP0621Generator lamp — circuit malfunctionguideP0622Generator field terminal — circuit malfunctionguideP0625Generator field terminal — low signalguideP0626Generator field terminal — high signalguideP0627Fuel pump relay — circuit malfunctionguideP0628Fuel pump relay — low signalguideP0629Fuel pump relay — high signalguideP062FControl module non-volatile memory errorguideP0630VIN not programmed or mismatchguideP0645A/C clutch relay — circuit malfunctionguideP0650Malfunction indicator lamp — circuit faultguideP0685ECU main relay — circuit malfunctionguideP0691Cooling fan relay — low signalguideP0692Cooling fan relay — high signalguideP0693Cooling fan relay 2 — low signalguide
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Other sections
Fuel and air metering, general 33Intake measuring sensors 17Oxygen sensors 19Throttle and accelerator pedal 15Mixture: lean and rich 11Fuel and air metering: injectors 25Ignition system and misfires 29Exhaust gas recirculation (EGR) 7Secondary air injection 3Catalytic converter 4Canister and purge valves 9Fuel vapour leaks 7Fuel level in the tank 4Diesel particulate filter 6Idle and auxiliary systems 22Transmission 17Communication between modules 20Brakes, ABS and stability control 17Body, airbags and lighting 12