P28C2: The ion detection module power supply voltage is above normal
The ion detection module power supply voltage is above normal. It usually comes from the battery, the alternator or a poor connection.
| Code | P28C2 |
|---|---|
| System | Engine and transmission |
| Group | P28xx, Transmission and engine |
| Type | Generic: it means the same on every make |
How to read and clear P28C2 with Final OBD
Plug an OBD2 scanner in under the steering wheel, switch the ignition on and open Final OBD. Under Faults you’ll see P28C2 with its description and whether it’s confirmed, pending or permanent.
This code is usually stored by the gearbox control unit. If the car reports it over standard OBD, you read it for nothing with FREE; to read it straight from the gearbox control unit, with its description and clearing, you need PRO.
Clearing the code only turns the light off: if the cause is still there, it comes back. Clear it once it’s fixed, and not right before an inspection. It’s all in how to read and clear fault codes and in inspections and OBD.
Similar codes
- P28BE The cylinder 12 ion current detection gives a lower signal than normal
- P28BF The cylinder 12 ion current detection gives a higher signal than normal
- P28C0 The ion detection module power supply voltage has an electrical fault
- P28C1 The ion detection module power supply voltage is below normal
- P28C3 High load purge line B of the fuel vapour system is not working properly
- P28C4 The clutch A motor phase U V W gives a lower signal than normal
- P28C5 The clutch A motor phase U V W gives a higher signal than normal
- P28C6 The clutch A motor phase U V W has a broken or disconnected wire
What does code P28C2 mean?
The ion detection module power supply voltage is above normal. It usually comes from the battery, the alternator or a poor connection.
How do you clear P28C2?
With an OBD2 scanner and an app like Final OBD, which clears it for free if it’s stored by the engine control unit. But clearing it only turns the light off: if the cause isn’t fixed, P28C2 comes back.
Read it on your car
Final OBD reads and clears engine faults through standard OBD for free, each one explained in plain English. With PRO it also reads the faults of every control unit, each make’s own codes included, and clears them in all of them.
