Lj78 2lte name that wire (3 Viewers)

[Postoy]

Ok so I swapped out my injectors today and decided it would be a good idea to test my glow plugs at the same time. Did all that, buttoned it all up and now the truck won't start. When I first turned the key on I fried a wire...


I replaced the burnt wire with the blue wire in the picture.. anyone know what it's for?
It is a thick black wire that seems to run into the firewall with what looks like the main harness. It is junctioned as you can see to the blue wire and hooked to the positive battery.
Does this even make sense?

 

[kbushnz]

So you replaced a burnt wire with the blue one which connects to the battery...
If that is correct the wire you replaced is no ordinary wire but what is called a fusible link.
Its a simple fuse.
Before you turn anything on I would be checking all your connections again as something big has shorted out.
You may have earthed out the glow rail....
And you will need to replace the new blue wire with a proper fusible link / wire as it will not blow at the correct current draw and will burn other wires in the system which are smaller.

 

[Postoy]

Ok thank you. So chances are I have burned other wires. I tried it again before I seen this and the truck still won't start. But I have hooked that wire back up and it isn't doing anything now. I take it that means other wires are burnt... now I get to dig I guess. .. great...

 

[kbushnz]

Hopefully you may have blown other fuses in the fuse bank in the truck. Would pay to have a look.
I can only assume you have connected up something wrong or the glow rail is earthed out. You will need to retrace your steps and look very carefully. Google is good to hunt out images of what things should look like.
There are two insulator washers that go on the connection stud for the power wire on the glow rail. if one or both are missing it will short out. Also check the glow fuse in the fuse box.

 

[kbushnz]

 

[kbushnz]

 

[GTSSportCoupe]

OUch. I've done that before too. When I mixed up the plastic isolators for the glow circuit at the intake manifold. Big puff of smoke. I replaced with new wire and it's been fine since.

 

[Postoy]

Ok any other suggestions? I spaced the glow rail as needed and replaced the wire. All fuses under the dash are fine. Still won't start. And when I manually switch on the glow plugs from my wired switch there is no draw on the battery... should this thing not start after cranking a bunch? Even if the plugs are not heating?

 

[kbushnz]

Will depend if anything else blew ... As its the 2lte... The engine fuel is controlled by an ECU...
You will need to download a manual and start checking for the presence of voltage at the various sensors and relays...\
It could be something simple, have you pumped the fuel filter lift pump to prime the system....
I know it takes a few cranks to get the fuel thru... and with no glow plugs to start off the combustion process you will find it difficult to start if not impossible...You could always manually glow it... Wire from battery to glow rail.... hold for a few seconds and get someone to crank her over...Bit crude but should work.

 

[GTSSportCoupe]

Ok any other suggestions? I spaced the glow rail as needed and replaced the wire. All fuses under the dash are fine. Still won't start. And when I manually switch on the glow plugs from my wired switch there is no draw on the battery... should this thing not start after cranking a bunch? Even if the plugs are not heating?

It's amazing how hard it can be to start these motors with no glow at all. Do you get puffs of white smoke out the back while cranking? If so, you are getting fuel, which means the computer is working to some degree.

If your glows are not working even with a manual setup, that is where I'd start if I was you. Check for 12V to the glow plug relays. Maybe there is still a problem in the wiring?

I'm assuming you did what I did and shorted the glow rail to the intake manifold? Really, that should not have damaged anything else. The rest of the circuits would have seen that as a 'brown out', just a drop in voltage.

 

[Rummat81]

been down this road.
do you have a multimeter? If not go to cdn tire / walmart and but 1 for 15/20 bucks. watch a video on how to use it.
pls ignore above if you have one.
1. disconnect both terminals of battery
2. find and disconnect the two relays for glow plugs, they are located on the inner fender. they prob say glow on them.
3. disconnect the two connectors for each relay.
4. check for continuity between battery and relay, and then between relay and bus bar. how have you wired your switch, does it splice into relay control wire?
5. after verifying continuity and fixing for burnt wire, check again.
6. connect battery and check for control voltage at switch.
7. carry one one thing at a time and check for voltage at each stage. Do the secondary glow relay separately,

I had a thread as part of cylinder head installation with some pics, i am not sure if the pics are there any more.

good luck.

 

[Postoy]

Found the problem!



Got it up and running again. Kinda jerry rigged it for now. I have to find new ends for this plug.

 

[Rummat81]

Just get a generic water tight plug that would accept the wire size 10-12 gauge maybe. I had the same thing myself. .

 

[GTSSportCoupe]

Found the problem!

Got it up and running again. Kinda jerry rigged it for now. I have to find new ends for this plug.

Nice work. I better check that connector on mine. Could be half burnt too.

 

[Postoy]

Good plan!
Does anyone know how many amps the 4 glow plugs draw? I replaced that fusible link wire with a fused wire. I originally had a 25 amp fuse in there but I seem to be poping those after a few days... or maybe from leaving the glow plugs on too long? I have switched it out for a 30amp.