Fixing MPC Electronic Remote Door Popper System
Read More
Since the driver's side door solenoid stopped working, I took the electronic control apart and with a volt/ammeter, traced the failure down to the printed circuit board mounted relay, which is labeled "40 amp", but clearly could not handle the load over many cycles. MPC wanted $70 for only a new electronic box. I decided there was a better way to solve the issue by installing separate replaceable plug in relays. Plus, if one or both relays fail again, it's an easy $5 fix.
Red wire is fused 12v constant power input wire. Large Blue wire to passenger side solenoid. Large Green to driver's side solenoid. Small blue and green wires to switches mounted inside the doors that make contact when one pulls the inside door handle . See "The Doors" Gallery. Black wire goes to Ground. Brown wire goes to trunk solenoid. Pink wire goes to parking light flasher. Yellow wire locks out the system when ignition is on so you can't open the doors while driving.
Four wires soldered to the two holding coil connections to energize two external relays. There is a potential problem with leaving the old relays in place. The PCB has triacs or whatever you call them, to trigger the original relays. By adding the external relays, those triacs then will see BOTH holding coils, possibly overloading and burning out those electronic devices.
So those relays both need to come out so the circuits to the holding coils are GONE. After cutting out the relays (with my Dremel) down near the surface of the PCB, I ohmed out the holding coil connectors to assure that those connections were GONE. Look closely at the contacts of one of the relays below the PCB. That set of contacts is clearly burned up.
External wiring completed and ready to see if this works, The board mounted relays do nothing now. Notice that the RED power wire that feeds both the electronics and the power source for the relay contacts are all tied together, and the output wires in the large white plug have been removed and connected to the contact power inputs for the new relays. The power outputs from the relays are now connected to the feed for each solenoid inside the doors.
