P0650: Malfunction indicator lamp (MIL) control circuit
The engine computer has found a fault in the circuit that switches the check engine light, so the light may not come on when it should, or may stay on.
Updated
What P0650 means
The engine computer switches the check engine light (the malfunction indicator lamp, MIL). On older cars it does so through a wire to a bulb; on many newer cars it sends a message to the instrument cluster over the network.
P0650 means the engine computer has found a fault in that circuit. The light may not come on when a fault is stored, or may stay on.
With the ignition on and the engine off, on most cars the check engine light should come on as a bulb check, and go out once the engine runs without faults.
Can I keep driving?
Check soon
Probably OK to drive short-term, but have it checked soon. The check engine light may not warn you of a new fault, so read the codes now and then until it’s fixed.
General guidance based on the code alone, not on the car’s actual condition. If in doubt, stop and ask a mechanic.
Until it’s fixed, read the codes now and then with Read My Car, so a new fault doesn’t go unnoticed.
At an inspection that reads OBD, this code means the OBD check isn’t passed. In the Dutch APK, for example, the inspector checks that the light comes on and matches the stored codes; if it doesn’t, or codes are stored, the car gets the usual exhaust gas test instead of passing on OBD. Have it fixed before an inspection.
Symptoms
- The check engine light doesn’t come on with the ignition on before starting.
- The light stays on, or flashes, without another code that explains it.
- Stored codes while the light is off.
Common causes
- Wiring or connector fault between the engine computer and the instrument cluster. On cars where the cluster gets the light as a network message, that includes the network connection.
- Fault in the instrument cluster, or a failed warning lamp on older cars. Older clusters use bulbs that can burn out; newer ones use LEDs or a display.
- Fault in the engine computer’s lamp circuit. Less common, and checked after the wiring and the cluster.
Typical fixes
- Switch the ignition on without starting, and check whether the check engine light comes on.
- Read the codes with Read My Car and see whether the light matches them.
- Have the cluster and the wiring or network connection to it checked; on older cars, the bulb.
- Clear P0650 after the repair, and check the bulb check again.
Questions
Can I drive with P0650?
Probably for a short time, but have it checked soon. The check engine light may not warn you of a new fault, so read the codes now and then until it’s fixed.
My check engine light works. Why is P0650 stored?
The fault can come and go, for example a connection that breaks now and then. Clear the code: if it comes back, have the circuit checked.