Symptoms:
-Glowplugs, all but one checks out within norms of ohmmeter, that one reads infinite, tested the relay and it is good, but they are not warming the engine. I even swapped the relay out on a lark, no change.
-engine lopes/romps
-I have continuity from any positive terminal when disconnected from the batteries to any place on the engine.
-Truck will start when warm out
-ABS light is on at all times
-CEL light still comes one when I force a fault
-No other interior electric works besides TAC and overhead cab lamp.
-Headlights will work
-turn signals will not work
-brake lights will not work.
-Batteries would drain if left connected overnight
-power door locks will click the relay under the dash, but will not activate the actuators
-blower motor for HVAC not functioning

It is my theory that the glow plug system is being bypassed by the short, because of the significant resistance difference.
The thing that gets me, is that I can still start the truck and run it with this short in the system. Any ideas?

 

I am pretty sure that you should have continuity even witht he batteries unplugged. This comes rom the alt. I said pretty sure, so I could be wrong. If there was a short, I figured it would have popped the fuse, or melted a relay, unless one isnt working. So when you have everything shut down, is there something working that shouldnt be? I.E. can you still roll windows up, does your windshield wipers still work, etc....

Have you load tested the batteries? Is it possible that waht you think is a short killing your batteries is really just a few bad cells in a battery? Just food for thought.

 

Was this the truck that was under water???

 

of course, it's my new learning experience.

I just do not see why the glow plugs would not engage, each read 1.2-1.8 ohms with the exception of passenger side rear which did not read at all.

 

Does this mean that with the batteries disconnected you have continuity to any part of the engine like the block, alternator case....

If so YIKES!! Todd mentioned the alternator. I would unhook the charge wire at the alternator and see if you still have continuity.

 

That is correct, and what is wierd, is that she will crank, start up, and run.

If removing the charge cable from the alternator solves it, does that mean my alternator diode is out?

 

WOW!! Start by unhooking the charge wire at the alternator. if you still have continuity unhook the starter cable. Next I would unhook the wires on the starter relay on the fender. This is gonna be a fun process of elimination

 

Hard to understand your tests.
Possible just testing continuity of the + circuits while batt disconnected?

I would venture time into investigating grounds.

The inf plug is bad.

Bill

 

TJ

Iam in the dark. Missed the posts.
Confused. Cont to ground?

Bill

 

Just unhooked starter charging wire, still continuity.

 

Bill this truck was completely submerged for over 30 minutes in a pond!! Who knows what we will find.

The more I think about this continuity thing the more I think its not really possible. You cables would burst into flames and the truck wouldn't start if both the neg and pos battery cables were grounded out. Tell us exactly how you are testing this please.

 

unhooked the wires at the starter relay. Continuity was gone. Rehooked them one at a time to systematically figure out which one... it was the largest red wire going to the terminal towards the front bumper....

 

Oops!

I dont have a handle on what.

I wonder if as of now it has a batt draindown isssue in off condition.
WAG

Bill

 

I am thinking that you shorted out a gem module, dont unhook the alternator hot lead without first unhooking grounds from batteries as you will probably take out the alternator too.

2002 F-350 CC Lariat 4x4 7.3

 

I placed one lead of the continuity detector on the positive terminal cable with the batteries disconnected I then placed the other end on the alternator housing... "beeeeep" then i moved it to the HPOP "beeeep" then the block "beeep." Make sense?

I do not know what it means, but would suspect it is a short in the system because the batteries will get drainined over time if left hooked up, and I am no expert on electric theory, but I am pretty sure the block is not supposed to have connectivity with the + terminal connector unless the truck ignition is in the start or run position. Is that right?