Tempomatic Cruise control questions
 

I have the standard W201 190E cruise control issue where the solder connections in the control brain box crack and the cruise control will work until it gets hot. Intermittently the cruise will turn off or it will surge back and forth. In order to fix the problem I thought that I would just get the coding plug and the newer style cruise control brain box that the EPC shows replaced the old no-coding plug style. I got a coding plug for my 1986 2.3-16v and a couple of the newer style cruise control brain boxes this week. I took out my currently working old style control box and replaced it with one of the new style boxes and the correct coding plug. Guess what, it doesn't work. I tried the second brain box and it does not work either. The original old style box still works just fine (til I go on a long highway trip and the contacts get warm). Is there anything special that needs to be done to get this swap to work or did I just get unlucky and get TWO bad control boxes from my used part supplier? The EPC show that both the part numbers for the two boxes I have as possible replacements for the OEM 0035450932 crusie box. Neither new style box works at all in the car. The original box still works.

Has anyone ever replaced their control unit without the coding plug for one with a coding plug? Was it a direct swap?

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