1, 2 and 3 Digit Codes: 39

Diagnostic Chart:

Trouble Code Number
- Scan tool 39
- MIL 13

Fault Message
- Slow Change in Idle MAP Sensor Signal

Background
- The MAP sensor is mounted to intake manifold vacuum.
- This information provides an important PCM input for determining fuel injector pulse wide.
- The sensor should measure a difference in manifold pressure between key ON and after the engine is running.

Range of Check
- Vehicle is not moving.
- Engine: The engine idle speed is almost identical to the target idle speed while the engine is idling.

Set Condition
- The difference between the MAP value immediately after the ignition switch is turned to ON and the MAP value while the engine is idling remains little for 2 seconds.

Probable Cause
- Ice in sensor
- Sensor failed
- PCM failed