98 F150 Electrical problems
98 F150 Electrical problems
Ready to pull my hair out (if I had any). Here's the scenario. About a month ago, tried to start the truck and got nothing. Jumped it and it worked fine for a while. Never found any rhyme or reason why, but it was working, so let it go. The last few weeks, noticed the 4WD switch would not do anything to put it in 4WD. Sometimes the window wouldn't go down. The heat only works on low or high, nothing in between. Nothing major, but PITA nonetheless.
So now we come to this past week. On Tuesday night, I'm sitting by a window which is next to the driveway and I hear a car starting in the driveway. I go outside and the truck is trying to start by itself, no keys, no one in it. Things are dinging, hissing, all kinds of noise. I pull the battery cables and let it sit. Today, I hooked it all back up and when I try to start it, I just get a loud CLICK and nothing else. Lights work, heater works, everything works(even with the ignition off and keys out), but won't start. The battery gauge shows full charge. I got underneath and noticed smoke coming from the starter. I disconnected everything and walked away. Someone, PLEASE give me some good news and some help here!!!!!!!!!
So now we come to this past week. On Tuesday night, I'm sitting by a window which is next to the driveway and I hear a car starting in the driveway. I go outside and the truck is trying to start by itself, no keys, no one in it. Things are dinging, hissing, all kinds of noise. I pull the battery cables and let it sit. Today, I hooked it all back up and when I try to start it, I just get a loud CLICK and nothing else. Lights work, heater works, everything works(even with the ignition off and keys out), but won't start. The battery gauge shows full charge. I got underneath and noticed smoke coming from the starter. I disconnected everything and walked away. Someone, PLEASE give me some good news and some help here!!!!!!!!!
The starting sounds like an issue with the Starter itself, but best to check the starter motor relay on the firewall under the hood.
Unhook the cable to the starter, and hook up the battery.
With the key out, check to see if there is power on both sides of the start motor relay ( the 2 large cables ). If +VDC is there, check the Tan w/ Red stripe wire to see if + VDC is there ( it is the small AWG Wire, the 3rd one on it )
If this tests OK, I would suspect there is something wrong with the starter solenoid ( on the starter, the "piggy back" item ).
As far as the truck looking like the key is on, I would suspect a windshield leak ( from the CT in the member name, and the news as of late ) from rain has soaked the GEM ( bolted to the back of the cab fuse panel ).
You might want to check for signed of water damage at the carpet, best place to check is behind the driver's side kick panel ( remove it, and pull back the carpet and check for water / rust ).
If you can, get the truck indoors ( or tarp the cab ) so you can get ti dried out. Some times drying out the cab of the truck will cure the GEM issues, other times it need to be removed from the back of the cab fuse panel, and replaced.
Those are the points I would start with, seems like 2 problems at the same time ( or the starter problem made you see the possible GEM problem ).
Unhook the cable to the starter, and hook up the battery.
With the key out, check to see if there is power on both sides of the start motor relay ( the 2 large cables ). If +VDC is there, check the Tan w/ Red stripe wire to see if + VDC is there ( it is the small AWG Wire, the 3rd one on it )
If this tests OK, I would suspect there is something wrong with the starter solenoid ( on the starter, the "piggy back" item ).
As far as the truck looking like the key is on, I would suspect a windshield leak ( from the CT in the member name, and the news as of late ) from rain has soaked the GEM ( bolted to the back of the cab fuse panel ).
You might want to check for signed of water damage at the carpet, best place to check is behind the driver's side kick panel ( remove it, and pull back the carpet and check for water / rust ).
If you can, get the truck indoors ( or tarp the cab ) so you can get ti dried out. Some times drying out the cab of the truck will cure the GEM issues, other times it need to be removed from the back of the cab fuse panel, and replaced.
Those are the points I would start with, seems like 2 problems at the same time ( or the starter problem made you see the possible GEM problem ).
The starting sounds like an issue with the Starter itself, but best to check the starter motor relay on the firewall under the hood.
Unhook the cable to the starter, and hook up the battery.
With the key out, check to see if there is power on both sides of the start motor relay ( the 2 large cables ). If +VDC is there, check the Tan w/ Red stripe wire to see if + VDC is there ( it is the small AWG Wire, the 3rd one on it )
If this tests OK, I would suspect there is something wrong with the starter solenoid ( on the starter, the "piggy back" item ).
As far as the truck looking like the key is on, I would suspect a windshield leak ( from the CT in the member name, and the news as of late ) from rain has soaked the GEM ( bolted to the back of the cab fuse panel ).
You might want to check for signed of water damage at the carpet, best place to check is behind the driver's side kick panel ( remove it, and pull back the carpet and check for water / rust ).
If you can, get the truck indoors ( or tarp the cab ) so you can get ti dried out. Some times drying out the cab of the truck will cure the GEM issues, other times it need to be removed from the back of the cab fuse panel, and replaced.
Those are the points I would start with, seems like 2 problems at the same time ( or the starter problem made you see the possible GEM problem ).
Unhook the cable to the starter, and hook up the battery.
With the key out, check to see if there is power on both sides of the start motor relay ( the 2 large cables ). If +VDC is there, check the Tan w/ Red stripe wire to see if + VDC is there ( it is the small AWG Wire, the 3rd one on it )
If this tests OK, I would suspect there is something wrong with the starter solenoid ( on the starter, the "piggy back" item ).
As far as the truck looking like the key is on, I would suspect a windshield leak ( from the CT in the member name, and the news as of late ) from rain has soaked the GEM ( bolted to the back of the cab fuse panel ).
You might want to check for signed of water damage at the carpet, best place to check is behind the driver's side kick panel ( remove it, and pull back the carpet and check for water / rust ).
If you can, get the truck indoors ( or tarp the cab ) so you can get ti dried out. Some times drying out the cab of the truck will cure the GEM issues, other times it need to be removed from the back of the cab fuse panel, and replaced.
Those are the points I would start with, seems like 2 problems at the same time ( or the starter problem made you see the possible GEM problem ).
The starting sounds like an issue with the Starter itself, but best to check the starter motor relay on the firewall under the hood.
Unhook the cable to the starter, and hook up the battery.
With the key out, check to see if there is power on both sides of the start motor relay ( the 2 large cables ). If +VDC is there, check the Tan w/ Red stripe wire to see if + VDC is there ( it is the small AWG Wire, the 3rd one on it )
If this tests OK, I would suspect there is something wrong with the starter solenoid ( on the starter, the "piggy back" item ).
As far as the truck looking like the key is on, I would suspect a windshield leak ( from the CT in the member name, and the news as of late ) from rain has soaked the GEM ( bolted to the back of the cab fuse panel ).
You might want to check for signed of water damage at the carpet, best place to check is behind the driver's side kick panel ( remove it, and pull back the carpet and check for water / rust ).
If you can, get the truck indoors ( or tarp the cab ) so you can get ti dried out. Some times drying out the cab of the truck will cure the GEM issues, other times it need to be removed from the back of the cab fuse panel, and replaced.
Those are the points I would start with, seems like 2 problems at the same time ( or the starter problem made you see the possible GEM problem ).
Unhook the cable to the starter, and hook up the battery.
With the key out, check to see if there is power on both sides of the start motor relay ( the 2 large cables ). If +VDC is there, check the Tan w/ Red stripe wire to see if + VDC is there ( it is the small AWG Wire, the 3rd one on it )
If this tests OK, I would suspect there is something wrong with the starter solenoid ( on the starter, the "piggy back" item ).
As far as the truck looking like the key is on, I would suspect a windshield leak ( from the CT in the member name, and the news as of late ) from rain has soaked the GEM ( bolted to the back of the cab fuse panel ).
You might want to check for signed of water damage at the carpet, best place to check is behind the driver's side kick panel ( remove it, and pull back the carpet and check for water / rust ).
If you can, get the truck indoors ( or tarp the cab ) so you can get ti dried out. Some times drying out the cab of the truck will cure the GEM issues, other times it need to be removed from the back of the cab fuse panel, and replaced.
Those are the points I would start with, seems like 2 problems at the same time ( or the starter problem made you see the possible GEM problem ).
I sure hope not. What are the chances that I replace the GEM/fusebox and windshield and everything goes back to working fine???
Best to pull the + VDC cables from the starter, and have it tested.
At this time, tape up the ends, and run the tests on the starter motor relay.
While you are under there, take a good look at the cables like papa tiger posted. Pay attention to the cable ends where the corrosion might be up the cable insulation a bit. Bending them, and taking a look will show this.
- If you have an issue, it could be the ring terminal will break off when you do this.
At this time, tape up the ends, and run the tests on the starter motor relay.
While you are under there, take a good look at the cables like papa tiger posted. Pay attention to the cable ends where the corrosion might be up the cable insulation a bit. Bending them, and taking a look will show this.
- If you have an issue, it could be the ring terminal will break off when you do this.
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I'm going to replace the starter and the relay/solenoid on the firewall. I still cannot find the water leak for the life of me. It seems to be coming from the very top left of the dash. There's a bundle of wires that go from above the GEM/Fuse panel up into the body. However, from there, I cannot see where it's coming from. This is the most frustrating thing I've ever run across in a vehicle.
Don't know if it is your source, but members report a issue with the windshield sealant on the driver's side along the A pillar.
If you pull the A pillar cover, you might see it from that side, but the posts by members was when they took the truck to a shop and had them pull the windshield to have it resealed, once the trim was taken off the area could be seen where the sealant had an issue.
Power roof panel was at least 1 member's source for his leak, it leaked down the a pillar not the drain tube.
If you pull the A pillar cover, you might see it from that side, but the posts by members was when they took the truck to a shop and had them pull the windshield to have it resealed, once the trim was taken off the area could be seen where the sealant had an issue.
Power roof panel was at least 1 member's source for his leak, it leaked down the a pillar not the drain tube.


