After removing my GEM and chasing a power drain I have a no start. At first it would turn over but no smoke, no start. It quickly turned to no turn over, no WTS and can't connect to the computer through the OBD.

I have checked all fuses and fuse pockets, I have power everywhere. Delay works for windows, dome light comes on and goes off as it should. Engine turns over when jumped across the fender relay. All aspects of the fuse box seem to work, which indicates proper reinstallation of GEM. Can work shift lever when stepping on brakes, 4x4 transfer case works as it should. Batteries are charged and holding 12.6 volts.

What to check next?

Thanks,
Mark

 

Does starter turn engine using the key? What about jumping the posts on the starter with a screwdriver?

 

No with key, yes with relay on fender. Which brings to mind, that small wire on the relay, is that a + or a -, should I try applying ground to it or power?

 

I would triple check all connections and fuses. Then start with one circuit at a time. Here is the crank circuit to help with diagnosis.

 

Let me know if you don't have power at fuse 20 (C243 pins 19 and 4) in the junction box when trying to crank and I will find where that power source is.

 

I have power on the one side of 20 all the time, when looking from the front of the truck it's the left prong. What else should I look for on that?

I have also discovered that while I have four way flashers I do not have turn signals.

And I have a question on the starter relay, maybe I have something wired wrong there. There are two wires that come off of the relay (besides the two large wires), one goes to the alternator and the other goes to the junction box. Then there is a smaller wire that ohms out to ground. I have both of those medium wires hooked to the power side of the relay. Is that wrong? What makes that relay work?

 

Mark, when I get home in a bit I can take a picture of the starter relay if you think that will help?

 

Sounds good, thanks.

 

I will be home around 1600 EST, should have a shot uploaded around that time.

 

Mark, here is a picture on my E99 of the starter relay. Any questions ask. This is pretty much stock so don't know if anyone has messed with yours. Hard to see in the picture but the two medium size wires goes to the rear (firewall) side of the big terminals. The smaller wire is a push on connector and is what actuates the relay with key. If you unplug that small wire you can jumper the relay screw type terminal to battery plus and that will activate the solenoid.

 

Looking at some stuff we discussed

You should be able to disconnect the "control" wire of that solenoid and use your test light to go from battery (+) to that post and the starter will crank.

Engine won't start, but that tests your solenoid. You can use a piece of wire, too, but the test light gives you a current-limited connection which is safer.

Make SURE the wire that belongs there is disconnected first. *probably* won't hurt anything, but better not to take a chance.

 

 

Here's a wiring diagram that I *think* would match your truck. Fender solenoid AND starter solenoid and how they wire up.

 

Mark- The top right MOUNTING bolt of the solenoid in Sous' pic is the one I want you to use your 12v VOLTAGE to test from battery (+) using your meter's red wire to that mounting bolt using the meter's black wire.

You should get very close to the same voltage you have between the battery's (+) and (-) posts. If not, you have a bad ground at that bolt, solenoid won't work until you fix the ground

 

Does one of these look like your GEM?

Top 2 pics or bottom 2 pics?

GEM module... Which one do I need? - Diesel Forum - TheDieselStop.com