W124 300TE A/C Blower fan is not working when the car is running

[ke6dcj]

Our 1988 W124 300TE A/C Blower fan is not-working when the car is running. If I turn-off the engine and put the ignition switch in position 2 WITHOUT starting the car, the blower fan works in HIGH, AUTO, and LOW, but once started the blower fan does *not* work.

All fuses checked OK and replaced 2-years ago. What get's me is it works when the engine is not running . . .

Any ideas?

Thanks,
:-) neil
1988 360TE AMG
1993 500E

[jcyuhn]

If I were a bettin' man, I'd bet on the ignition switch. Seriously, try jiggling/wiggling/otherwise adjusting the ignition after starting the car, see if the fan starts. Otherwise, try to determine whether the PBU has power after starting the car. One way would be to check the monovalve. It should be supplied with 12v whenever the PBU is placed in the 'off' mode.

Happy troubleshooting,

- Jim

[ke6dcj]

Yep, it's the ignition switch. I've checked the W124 Service CD-ROM, and I can't find the procedure to replace the ignition switch.

I did find 46-8010, "Removal and Installation of Steering Lock- Complete". It seems excessive. . .

Anyone done this before and can explain generally the procedure?

:-) neil
1988 360TE AMG
1993 500E