M102 AUX Fan Sensor/Switch - Wiring Diagram
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From: Cape Town, South Africa
1992 W124 230E Auto
M102 AUX Fan Sensor/Switch - Wiring Diagram
I'm sitting with a strange problem on my '92 W124 230E which I can't seem to trace:
Does someone perhaps have a wiring diagram that shows the above switch relative to the relay. It's not the same as the wiring diagram that shows relay K8 powering K9, getting its Ground from the Automatic Climate Control unit.
- My AUX fan comes on at full speed intermittently with the ignition on, particularly if the engine is warm, but below operating temperature. I don't have Automatic Climate Control;
- The AUX fan (full speed) is supposed to be triggered by switch 006 545 9124 at around 110 degrees C, yet it keep on running even if I disconnect the connector from the switch. The switch is receiving 5V. On this car the single pin on the switch activates the temp gauge, while the double pin activates the AUX fan at full speed at 110 degrees C;
- Relay K9 (001 542 0219) is receiving full battery voltage via socket terminals '30' and '86';
- The relay clicks when removing and refitting (at this point the AUX fan also briefly clicks).
- The relay has also 'chattered' activating the fan intermittently.
- If I remove the relay and bridge socket terminals '85' and '86' I get battery voltage, it makes no difference if the connector to switch 006 545 9124 is on or off, or if I bridge the connector terminals;
- If I bridge the connector terminals going to 006 545 9124, the relay clicks and the AUX fan runs at full speed.
Does someone perhaps have a wiring diagram that shows the above switch relative to the relay. It's not the same as the wiring diagram that shows relay K8 powering K9, getting its Ground from the Automatic Climate Control unit.
