Checking Change In Idling Speed on Engagement of A/C Compressor

Checking Change In Idling Speed On Engagement of A/C Compressor, not ETS (Electronic Throttle System)

Fault symptoms
Engine speed drops on engagement of A/C.

Tools:
- Breakout Box 8611 006

Before this check is performed, checking of the idle air control valve must have been carried out, see "Checking the idle air control valve". Testing and Inspection

1 Connect Breakout Box 86 11 006 to the LH control module.




2 Make sure that the gear lever/selector lever is in neutral and that the A/C or ACC is OFF.

3 Unplug the connector from the A/C compressor.

4 Start the engine.

5 Connect a jumper lead across:
LH 2.2
pins 9 and 16
LH 2.4,2.4.1, 2.4.2
pins 9 and 14 (not ETS).

6 Check the engine speed.

If engine speed does not increase:
Try fitting a new LH control module.

If engine speed increases:
- Check that voltage is present on pin 30 of the A/C relay holder. Check that there is no open circuit in the wiring between pin 16 of the relay holder and pin 16 (LH 2.2) of the LH control module/pin 14 of the relay holder and pin 14 (LH 2.4,2.4.1,2.4.2) of the LH control module.
- If voltage is present on pin 30 and there is no open circuit in the wiring to the LH control module, check the operation of the A/C relay.
- If the relay is in proper working order, try fitting a new LH control module.