2006 F550 idle control, ZF6 Heads up.

[lmorris]

I had the pleasure of installing a high idle on a newly constructed tow truck last week, don't ask me why they bought a used 2006 F550 to do this too. I hooked up the required 12v to the PTO wire, left the reference circuit open because customer asked for the lowest RPM available, and no high idle. Checked all inputs to PCM and checked for 12v at PCM connector, all good, no high idle. Go through the body builder's manual for any further information, nothing to help me there, so we ordered in a PCM. Still no go. Brought it up with our other diesel tech and he mentions he had one long ago that required a resistor to work, didn't recall anything specific though. So I put in a resistor for 1250 RPM and low and behold it works. Went back through the body builder's manual and it states nothing that a diesel engine with a manual transmission requires a resistor, only GAS engines. They took the truck with the new PCM anyways.

[Keith Browning]

Um, Bulletin Q108 is the one you want. It explains the SEIC functions in great detail including parameters, acronyms, circuits and there is a handy dandy little chart with resistor values for this feature.

 

 

Q108.pdf

[lmorris]

I started to read that, but stopped once I realized it is the same as the PDF in the body builders manual. Reading further this time I found the issue. In the bulliten it has the "manual transmission" discalimer for diesel and not gas. On the body builders web page it is listed wrong. Thanks for the info. Will have to go have a chat with someone on this issue.

[Aaron]

Good to know, we were going to put the pto sense on my buddy's pickup with a ZF just for warmup, I guess we will have to swing by radio shack first.