help!
Thread Starter
|
Senior User
Joined: Jan 2006
Posts: 162
Likes: 0
help!
my glow plug module went out and after testing all my glow plugs i determined that they were bad too. i ordered up a new module and glow plugs and replaced them all today. i connected the battery back up and somewhere in the plastic case of wires that go from the module to the battery, it started smoking. i unhooked the battery and tried to figure out what was going on without any luck. then i tried to start the truck up and after the wait to start light went off there wasn't any glow plug clicking at all. i'm afraid i might have friend my brand new module.
anybody have a clue what might be going on?
anybody have a clue what might be going on?
Tuned
Joined: Oct 2004
Posts: 250
Likes: 6
From: new york
The most common place where they smoke is the big connector on the passenger side. Its where the engine harness connects to the truck harness. There are 2 bigger yellow wires that provide the current to the glow plugs Via the relay, on most older trucks the spade terminals inside the black commector can become corroded and cause them to heat up. I've seen many of these connectors melt at this connection. It can melt to the point where these wires will short to other wires, If it is bad you will need to remove the bigger yellow wires from the connector and reconnect them with new ends or just a butt connector, if you peel back the harness on both sides you can usually get enough slack in the wire to reconnect them.
When you disconnect the engine connection if all the terminals are clean and there is no sign of melting I would next check the engine side of the harness inch by inch looking for chaffing or wear through especially where it goes over and under the injection lines. Since you already replaced the glow plugs and controller tthese connectors should be ok.
When you disconnect the engine connection if all the terminals are clean and there is no sign of melting I would next check the engine side of the harness inch by inch looking for chaffing or wear through especially where it goes over and under the injection lines. Since you already replaced the glow plugs and controller tthese connectors should be ok.
Post Fiend
Joined: Nov 2003
Posts: 21,285
Likes: 15
From: Nutter Fort, WV
Check the connector in the wiring harness that farmnfly was speaking of, it should be located in the general area of the engine oil dip stick. Do use caution, if the battery cables are hooked up, there will be battery voltage on the yellow wires at all times.
Also you need to inspect the wire loom from the battery to the engine, you may have a fuseable link in the harness that toasted. Look for signs of melting or overheating.
Post Fiend
Joined: Nov 2003
Posts: 21,285
Likes: 15
From: Nutter Fort, WV
Look at the connector closely, do you see where it is melting on the end that has the two large yellow wires on it?
They are the power to the glow plug relay. Cut them off as close as you can to the connector and resplice them together with split bolts or butt connectors. You should be back in business.
Usually the rest of the wires in the connector will be OK and still making contact. They carry nowhere near the power the glow plugs use.
They are the power to the glow plug relay. Cut them off as close as you can to the connector and resplice them together with split bolts or butt connectors. You should be back in business.
Usually the rest of the wires in the connector will be OK and still making contact. They carry nowhere near the power the glow plugs use.
Thread Starter
|
Senior User
Joined: Jan 2006
Posts: 162
Likes: 0
thanks for the help.
is there a way i can test my glow-plug and module to see if they're still working?
is there a way i can test my glow-plug and module to see if they're still working?
Trending Topics
Post Fiend
Joined: Nov 2003
Posts: 21,285
Likes: 15
From: Nutter Fort, WV
Get power to the controller and it should work.
Test the glow plugs with a test light to see if they are OK.
Test the glow plugs with a test light to see if they are OK.
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
AEV FXL Super Duty - the Super Duty Raptor Ford Doesn't Make
Brett Foote
Lobo Vs Lobo: Proof the F-150 Lobo Should Be Even Lower!
Michael S. Palmer
Ford's 2001 Explorer Sportsman Concept Looks For a New Home
Verdad Gallardo
10 Best Ford Truck Engines We Miss the Most!
Joe Kucinski
2026 Shelby F-150 Off-Road: Better Than a Raptor R?
Brett Foote
2027 Super Duty Carhartt Package First Look: 12 Things You NEED to Know!
Michael S. Palmer
10 Most Surprising 2026 Ford Truck Features!
Joe Kucinski
Top 10 Ford Trucks Coming to Mecum Indy 2026
Brett Foote
5 Best / 5 Worst Ford Truck Wheels of All Time
Joe Kucinski
Thread Starter
|
Senior User
Joined: Jan 2006
Posts: 162
Likes: 0
sorry for the bad quality, but here's a picture of the harness.
it looks pretty obvious that it was those two big yellow wires that got hot. my first question is, why has this never happened before, and suddenly happened when i hooked my battery back up after i switched out the glow-plug module?
and sorry dave, but i don't understand what you mean by respliceing them together with split bolts or butt connectors.
it looks pretty obvious that it was those two big yellow wires that got hot. my first question is, why has this never happened before, and suddenly happened when i hooked my battery back up after i switched out the glow-plug module?
and sorry dave, but i don't understand what you mean by respliceing them together with split bolts or butt connectors.
Tuned
Joined: Oct 2004
Posts: 250
Likes: 6
From: new york
You need to cut the yellow wires off on both sides of the connector as close as possible to the connector. Then strip back the insulator on on all four ends and then install a crimp on wire connector or if possible and much better soilder them together. You will need to cut back the protective loom, harness back a couple inches on both sides to get the extra length you will need to get the wires back to gether.
These wires always get hot on older trucks, you will never notice it untill they get to the point of smoking. I have seen several trucks that have had them spliced together!
As to why they smoked when you hooked up the battery I can't honestly say I know why, in the picture the wires don't look as bad as some Ive seen. If they could possibly melt to the point that they shorted other wires that triggered the glow plugs?
Make sure after you make the repair that you just momentarly install the battery cable, if it sparks alot you have too much load- a problem somewhere most likely where the wires melted the most. good luck
These wires always get hot on older trucks, you will never notice it untill they get to the point of smoking. I have seen several trucks that have had them spliced together!
As to why they smoked when you hooked up the battery I can't honestly say I know why, in the picture the wires don't look as bad as some Ive seen. If they could possibly melt to the point that they shorted other wires that triggered the glow plugs?
Make sure after you make the repair that you just momentarly install the battery cable, if it sparks alot you have too much load- a problem somewhere most likely where the wires melted the most. good luck
Post Fiend
Joined: Nov 2003
Posts: 21,285
Likes: 15
From: Nutter Fort, WV
Do all the rest of the gauges, oil and temp work OK?
That one looks like it was rather hot.
Someone posted that he had a clamp meter on his glow plug harness when he turned them on.
Initial draw was over 200 amps and then started to decline from there as they warmed up.
I don't know if that number is accurate, but I do know that is a tiny wire to carry 200 amps at 12 volts. All it takes is a little resistance in the connector and you get a lot of heat real fast with that many amps.
.1 Ohms resistance with 200 Amp draw = 4000 watt soldering iron.
That one looks like it was rather hot.
Someone posted that he had a clamp meter on his glow plug harness when he turned them on.
Initial draw was over 200 amps and then started to decline from there as they warmed up.
I don't know if that number is accurate, but I do know that is a tiny wire to carry 200 amps at 12 volts. All it takes is a little resistance in the connector and you get a lot of heat real fast with that many amps.
.1 Ohms resistance with 200 Amp draw = 4000 watt soldering iron.
