Purchased used working acc servo and amp on eBay, installed and worked for a few hours, then no heat. Replaced amp again and aux water heater and still no servo noise or heat, did I fry the servo, can I test servo and amp to see if they work? Ideas?

Thanks in advance

Have you removed and inspected all the fuses? There is also a small glass one in a capsule near the ice cube relays on the fender.

__________________

cooljay, I have checked the fuses in my fusebox, the two loose fuses in the fusebox, one is supposed to go to the aux. pump, and the other to the acc amp, is this correct? Where is this fuse on the fender next to the ice cube relays? Also, I have put 12v and ground to the servo on terminal 4 and 5 and the motor turns the gears, I have soldered the loose resistors on acc amp and measured 12v's at the electrical plug to the servo, but when I put in the amp the servo still does not turn. I will go and look for the fuse on the fender, let me know if you have more ideas and thanks man..

Cooljay, so I bypassed the servo valve coolant hose hookups by taking off all the hoses to the servo and coupling them together so that I have heat for now. All the other connections to the servo remain, so I put in the amp for another try and bam, the servo is working... so is the vacuum to the coolant temp switch on the bottom of the servo bad, or my vacuum is not that great, I measures 13-15 in/mg at the main vacuum pump line, cool to be progressing though... thanks again for the input..

The 2A glass fuse should be under the black cover on the driver's fenderwell, in an inline fuse holder, beside one or two ice-cube relays.

__________________


Mac
2002 e320 4matic estate│1985 300d│1980 300td
Previous: 1979 & 1982 & 1983 300sd │ 1982 240d

“Let's take a drive into the middle of nowhere with a packet of Marlboro lights and talk about our lives.” ― Joseph Heller, Catch-22

Maybe when you bypass the servo, you hit a lose or bad vacuum line and it caused the system to work. This system relays on vacuum alot and there are a ton of things that can cause a leak on this model..

__________________

Thanks, howhot is the amp supposed to get, my is almost to hot to touch, seems too hot?