As we finalize our plans to get the GMC project underway, there are always a few setbacks - Like being able to drive or move it!  Such is the case with a recent melt-down of the diodes under the suspension switches.

After some conversations with Jim Bounds, his analytical and diagnostic skills appear to have our coach close to being back on the road.

Jim sent me one of his "short" instructional emails... I did exactly as Yoda instructed - connect this, check that. Disconnect this, check that. Lo and behold it appears his plan narrowed things down to the relay at the compressor. I'll know for sure  when I switch that out.

Here's the picture of the initial melt-down of the diodes. The connectors are melted too so they have to go.

I left things exposed and hard-wired a few sacrificial diodes to see if that was the problem or if it was down-stream. They melted upon ignition.

Here are the new connectors installed. All clean and pretty. When I removed the switch panel, I discovered an old towel that had been stuffed into the wall to hold up the map pocket. It was hard, moldy, crusty and well - disgusting.

Here are the diodes prepped for installation. They MUST be installed with current flowing in the correct direction. As I write this, I'm going to check again to make sure!

Looks okay in this picture - the diode stripe to the striped wire. Notice two wires have black tape around them - that's so the left and right don't get confused.

After checking for tight connections, everything looks good and I cover with electrical tape for insulation.

Here's the culprit under the back sofa by the air compressor. That relay appears to be defective. Jim sent me four different part numbers and the auto parts store scratched my head until his computer found the Everco relay. Just the same, I'll call Jim to make sure - one melt down is enough. No fires are even better.

This is the harness that goes into the relay. I have to check the original electrical schematics to make sure some one along the last thirty plus years didn't make some change that is a problem as well.

Well - the relay is on order. The chassis battery is refusing to hold a charge. That's another problem - but I'll deal with that once I can get the suspension "up" and running - sorry, I couldn't resist! More as it develops...

PS - All GMC owners CLICK HERE for an important note on GMC wiring and a potential fire hazard. It's a flaw in the original design and Jim has an easy fix for it!