Hello all - In my Diesel collection I have this pristine 86 Trooper II w/C223T. But it has developed a problem over my last trip of 4 month - it will not turn-over. No power to anything except headlight. Battery load test is excellent, all fusible links, bat. connection (all the obvious) no glow plug kick in ZIP!. Ideas? This is probably a quirky problems as the vehicle is imaculate and always garaged. The Chilton manual I have just does not cover the oil burners well at all. Thanks! [color:"black"]

I'm looking in my '86 shop manual, so let's see if I can help you chase this one down:

You say you have power to the headlights. Do you have power to any other lights such as parking lights, brake lights, instrument lighting when you step on the pedal or turn the headlights on?

Do the headlights react at all when you turn the key to the start position? (I'm guessing probably not, but never hurts to ask)

If you have absolutely no other power evident in the truck, check the brown fusible link coming off your battery again. If that still shows good, check at the ignition switch for positive voltage coming into the circuit. The powered wire should be a white one according to the schems. If no, but your link is hot, then you probably have a break somewhere in that wire prior to the ignition.

If you're hot at the ignition switch, check for voltage at both positions of the headlight switch. There should be two hot wires going to the switch. This wire should again be white according to the book. The positive for the headlights should be red. If you have power to the ignition and the headlight switch, I'm going to guess that your ignition switch has failed and won't feed power to any of your engine relays or much else.

From the diagram though, I'm much more inclined to feel you have a blown link or a break somewhere in the circuit shortly past it. That circuit seems to feed practically every lighting and management circuit on the truck, except the headlights which only share their circuit with the alternator.

Please keep in mind that I'm just reading the provided schematics to the best of my ability and have not dug into these circuits in any meaningful way on my own. As such, I can't swear to wire colors, utilization order, or much else with absolute surety.

Hopefully this novella might help. If not, let me know and I'll keep digging through and see what I can find for you.

Good luck,
James

Thanks for the reply - will try to answer in order. Power only to Headlights absolutely nothing else. Headlight do not dim when ignition is activated. Fusible links are both good (think block 12, 52) Have not pulled ignition switch as it looked like a PIA to do. Will check white wire. Is there a resistance test for the engine relay and the xxx relay in the fuse box? How does the power loop from the battery through the starter on this engine.

Thanks again for diging in the bookwork!

I've been digging for you, but haven't found a test procedure for the relays. I have a sneaking suspicion that in the shop, they're more likely to do a pull and plug type check than actually test the relay itself, but I could be wrong.

The starter circuit on the Turbo Diesel is battery direct to starter, starter to ground. The starter relay circuit is ignition to relay to starter to ground. As far as primary cranking power for the starter, there doesn't appear to be anything else on the circuit, but if you've lost power to the ignition circuit, the relay won't ever close to allow power to the starter motor. From the looks of it though, as the starter solenoid is integral to the starter chassis, you should be able to test for positive power at the starter terminal.

It really does not seem that there is a likely candidate for your problem other than the ignition circuit. Nothing else really covers the range of systems that you're seeing down. As you have no lights at all, I'm more convinced as to it being a break in this line somewhere downstream of the fusible link before the ignition circuit, but I could be wrong. I doubt it's on the ground side since your headlights ought to be fed to the same ground side as everything else. Headlights not dimming when you turn the key would indicate that there isn't even a start of a power drain, so a frozen starter or something of that nature's likely out.

The diagram shows the starter relay closer in the circuit to source (battery) than the ignition switch, but doesn't say whether that's one of the relays in your fuse box, or if it's actually at the starter itself. That may be an easier place to check for voltage.

See if any of this works and we'll go from there.

James

Sunday morning brought the T/D back to life. After disassembly of the dash to gain access to ignition the white wire was without power. Following the white wire back -under the battery a positive lead from connector splits off into two (Ignition)(Kiki/engine relay). Evidently over time the battery dripped a little acid on the ignition side of that connector to destroy it. Didn't go back with OEM -but a close suitable replacement.

Thanks for the wiring help!

John K