P1661
MIL Control Circuit Conditions
Severity
⚠️ MediumCan you drive?
Yes, but get it checked soon
Approx. repair cost
$6–56 (est.)
Symptoms
- Check engine light does not come on when starting
- The check engine light is constantly on
- Check engine light flashes
- Unable to read fault codes
Causes
- Open or short circuit in MIL control circuit
- Engine control module (ECM) malfunction
- Problems with connectors or wiring
- MIL lamp failure
- Power or grounding problems
How to Fix
- Check the integrity of wiring and connectors in the MIL circuit
- Check the MIL lamp on the instrument panel
- Check MIL circuit power and ground
- Flash or replace engine control module (ECM)