Date registered: Sep 2012
Vehicle: 1972 Mercedes Benz 250
Location: Santa Fe, NM U.S.A.
Mentioned: 0 Post(s)
Quoted: 17 Post(s)
Symptoms of a failing Ignition Control Module?
What are the symptoms of a failing control module? Is it possible for it to work and then not work and then work again? The car started right up, and as I slowly pulled out onto the road from my driveway I hit the accelerator and the car pulled hard as usual then almost immediately the car died. I tried to restart and nothing. Luckliy, I was only about fifty feet from my drive way and a friend help me push it back. First thing that I checked for was spark. There was nothing at the plugs or coming out of the coil. I assumed it might have been the coil so I orderded one up because this the one that is on the car is the original 40 year old coil. Today, I had a chance to pull out the trusty meter and started to diagnose the problem. With the ignition on, I seperated the contact on the points and checked for any voltage reading from ground to the positive wire on the coil, there was nothing.(per Haynes book) I checked the ignition switch to see if everything was plugged in tight, it was. Checked for continutiy on the resistors, they were fine. So I decided to pull out the control module, everying was plugged in tight. I removed the screws from the back of the moduel and peaked inside. Although everything in there was covered with a redish brown "sealer" nothing looked like it had burned out. I put the cover back on and hooked it back into the car. With the ignition on, I checked with my meter again, one lead on ground and the other to the positive wire on the coil and now, it's showing power. I got back in the car and it started right up! Any thoughts or suggestions? My friend that was helping me had accidently dropped the module on the ground, that couldnt have got it back to working order? could it? Isn't it all solid state? What are the symptoms of a failing ignition module?