DTC 49 - Mil (Service Throttle Soon Light) Circuit Fault: Notes
The SERVICE THROTTLE SOON light should always light when the ignition is on and the engine is not running for 2 seconds. The PCM controls the MIL and makes it light by providing a ground path. DTC 49 will set when:
- Ignition voltage on the SERVICE THROTTLE SOON light control circuit when the PCM is requesting the SERVICE THROTTLE SOON light on.
Or
- No ignition voltage on the SERVICE THROTTLE SOON light control circuit when the PCM is requesting the SERVICE THROTTLE SOON light off.
PCM will default to the MIL will not light, but a current and history DTC 49 will set.
NOTE:
Test numbers refer to numbers on diagnostic chart.
- This step checks the PCM's ability to command the SERVICE THROTTLE SOON light.
- This step determines if an open is present in the ignition feed circuit or the SERVICE THROTTLE SOON light control circuit.