Spare ECM?

[Glennman]

Recently, because of the experiences of mqbus whose transmission puked, I obtained a spare control module for my Allison B500. I had it calibrated to be identical to the one in my bus.

Yesterday while looking at the wiring harness that serves the Jakes (still working on those), I pulled one of those metal connector guards at the end of the ECM. Each of the two guards are held on by two small bolts. When I removed the bottom bolt, a small amount of oil came out. Prior to replacing my air compressor and the oil pan gasket, I had some pretty good leaks in that area. I don't know how oil would be there except to assume that it entered through where the connectors enter the ECM.

Short of removing the ECM and looking inside (it's scary in there!), since the bus is running good, I thought of picking up a spare ECM and have it calibrated the same as the other. I'm thinking of contacting Fowler's in Connecticut to see if they have any available ECMs. I think it would be nice to have a spare in case something goes south. I hate the idea of removing the old one without having a backup plan. I have some pretty far trips planned this summer and having a few extra parts on hand is comforting. Any thoughts on this???

[luvrbus]

You can usually find those on EBay from $150 to $400.00,the perimetries are all the same for the B500,you just toggle for the feature you want since the B500 is only found in buses, the WETC generation is the thing to watch out for     

[Iceni John]

A few years ago I bought a spare DDEC ECM for my bus from Zacher's Bus Salvage in Harbor City CA:  it had been in a similar bus to mine that had been driven to their yard to be dismantled, so it should be in good working order.   It even still has all its connectors (the wiring harnesses had been cut off).   I believe in the umbrella theory:  if you have it you probably won't need it, but if you don't have it, guess what...

John     

[luvrbus]

The Allision World the ECM's are durable as they come 99% of the time it is the shift pad that gives up the ghost, I carried a extra shift pad but never the Allision ECM,the module will give a warning throwing the dreaded cat eyes