I am working on an 84 K5 6.2 diesel that is a military surplus with the 24V system. the glow plugs will not cycle. It has the controller that looks like a computer board under the dash. I have power to the Glow plug relay with the ignition on, but the controler won't ground it out. The temp sensor is brand new, the controler is brand new and the solenoid is brand new. This was someone else's headache that got dropped off on my steps. As far as I can see, the wiring is good, the only thing is there is a 16 gauge single light blue wire with a locking barrel connector that doesn't have anything to plug into. It is coming out of the Glow plug control harness...Any Idea where it goes?

I don't know about the blue wire but I had the same problem with mine and I found a small ground wire at back of engine that was broken. Fixed that and has been working good since

which side was the ground on? was it part of the glowplug harness or was it part of a different harness? Thanks for the tip...Craig

check the 2 large orange wires with a volt meter at the bottom of the glow plug relay when the key is first turned to the on position.

Don't know about the military trucks as they had a different glow plug system which I'm not too familiar with, but I know on the civilian trucks there was a ground strap from the back bolt on the intake manifold on the passenger side to the cab. If that gets broken the glow plugs won't work.

check the 2 large orange wires with a volt meter at the bottom of the glow plug relay when the key is first turned to the on position.

I have power to the batt side of the glow plug relay, no power to the glow plug side. Power to the energising small post on the same relay with the key on, but no ground to trip the relay. There are only three components that are plugged into the glowplug harness: the controler, the relay (solenoid), and the temp switch...The civilian wiring harness is different. Any military 6.2 owners out there?

Does anyone have a wiring diagram for an 84 military blazer? I am going nukin futs!

GO to the website www.steelsoldiers.com (http://www.steelsoldiers.com) and download

TM 9-2320-289-20 (http://www.steelsoldiers.com/index.php?module=pagesetter&type=file&func=get&tid=1&fid=file&pid=8) from page 854 to 884 shows electrical diagrams of 940 pages in the manual. Make sure at the bottom of each diagram you use it states "All except M-1010" . The Chevy "blazer" military model is not actually a Blazer to the military it is a M-1009 model.

Jim