Code 29 (Idle Actuator)

IDLE ACTUATOR CLOSING CIRCUIT
Explanation
This trouble code is stored when a break or short occurs at:
- Idle actuator
- Output stage in the Digital Motor Electronic (DME) control unit

The trouble code 29 is additionally stored in the case of a break in the voltage supply or plug-and-socket connection to the idle actuator.

NOTE: trouble code 29 can also be stored when engine operation is interrupted abruptly without the ignition being switched off beforehand. The defect is then detected at an engine speed < 600 rpm.

Troubleshooting
- Perform component activation with tester. The idle actuator is then activated at one second intervals. If there is no response, connect test adapter 61 1 491 or equivalent between the wire harness and idle actuator. A voltage of approx. 12 V should be measured at terminal 2. The value between terminal 1/2 is >10 V.
- Proceed with displayed scan tool diagnostic instructions if applicable.