Defrost button intermittent
 

I have a 88 300 TE where the defrost button is intermittent. If I press a little harder, sometimes having to hold it down, the blower works as normal. If the pressure is reduced, sometimes it stays on, sometimes it stops blowing. Is the control panel repairable? Seems to be a contact problem that may need a little tightening internally. Can the panel be taken apart without special tools.

If not repairable, would a 89 panel work on the 88? Not sure if the electrical plugs are the same as the part number appears to be different. Just took out the original part, appears to be rebuilt with 124 830 18 85. The part I can get is 124 830 32 85. Interchangable?

Thanks for any comments.

Check for cracked solder joints where the switches are soldered into the circuit board (6 terminals per switch). Also check and re-solder where the temperature wheel potentiometer is soldered in (3 or 6 terminals depending on manufacturer and version).

Have a look through TnBob's threads he did some repairs to W123 switches - you might get some tips and hints there.