Electrical problems. 81 240D. Exhausted.
 

I have two immediate concerns with my 81 240D. Unfortunately both are electrical and despite my delving thru much stuff in the search results I cant find anything that might help me much. Of course that could also be because where electricity is concerned I'm on very dangerous ground. So I'm asking for the forums help.

1) My aux fan stays on permanently. This just started on Friday after a month of driving without it. What would make it stay on permanently? With the ignition on that is. Neither my ventillation fan nor the AC works so I've not tried using those at all. Is the 240D the same as the 300's in that the aux fan appears to be activated by the AC system? I'm not really worried from the engines point of view as I'm in Phoenix and summers here so any extra engine cooling can only be a good thing right? I just dont like something with a mind of it's own.

2) My reverse lights dont work. This is a manual transmission not auto. Does the manual have a switch in it that activates the reverse circuit as I assume the auto does? It's not the fuses as they are all good and other stuff would apparently also be affected if these fuses (one for each side) were blown.

- Peter.

The pressure switch on top of the dryer has probably gone bad making the fan run all the time the ignition is on. As for the reverse lights, check the connection on the side of the transmission. I've run across this before (on an auto) where the simple fix was to remove the plug and clean the connection. Make sure both bulbs are good.

The reverse light switch for the manual trans is right underneath the shift boot, its a lil pin that sticks out and when u shift in to reverse, the shift knob pushes the switch in

I have seen temp switches in the head go bad and set the fan to running on other MB engines. Usually a two element type that has three pins in it.

Suggestions
 

Thank's for the suggestions folks. I shall look to them forthwith.

- Peter.