Relays on circuit board of ACC-II controller
 

I have searched this site but I have not seen where someone has replaced a bad relay on their ACC controller, also known as the CCU. Mine is an ACC-II for an 84 300D.

Does anyone know of a source and model # to use for replacing a relay on the circuit board?

Thanks

Are you sure it is a defective relay? Usually the solder cracks around the 5 terminals on them. Resolder all relays as well as the joints between the main board and the two boards that are mounted at right angles to it. Add a bit of fresh solder but take care not to bridge between traces.
Also a must for these cars is to add a series fuse in the auxiliary water pump circuit as it can badly burn the pushbutton assembly if (when) it seizes. I think I added a 1 or 2 amp fuse.
If you indeed have a defective relay, probably someone has a used one that they can send you. If you can't find one I can give you one for the price of shipping but it would be coming from Canada so hopefully you can find one closer.

For your reference. '84 should have the ACC-III.

My recommendation would be to get another relay from another used control unit.

I believe the 126 unit is similar and would afford you some relays.


Here are some pics of a set that I repaired for a customer:
W126 Climate Control Repairs - Imgur

Sorry, yup it is the ACC-III.

I will be re-soldering all the connections. I thought that I had 1 bad relay, but further testing shows it is OK I think. I also just noticed it is a Bosch relay, with a part number on it. I need to see what I can dig up on the part number.

I do have a spare board that I can scavenge for parts if needed.

Thanks for all the help.