What is this?
FTE Legend
Joined: Nov 2015
Posts: 30,870
Likes: 4,112
From: Angier, NC
It looks tobe on the wrong side to be a jumper for the NSS if you have a manual transmission and would think it would be inside the cab?
Over on that side I would think if you had factory AC it would got to the HVAC say the fan?
I cant remember now on my 81 but the factory AC was a add on harness to the main harness and think there was a jumper if it did not have AC.
With out the jumper the blower fan would not work. Mine was inside the cab but yours?
Dave ----
Over on that side I would think if you had factory AC it would got to the HVAC say the fan?
I cant remember now on my 81 but the factory AC was a add on harness to the main harness and think there was a jumper if it did not have AC.
With out the jumper the blower fan would not work. Mine was inside the cab but yours?
Dave ----
Cross-Country
Joined: Feb 2021
Posts: 64
Likes: 32
From: Fort Knox KY
I'm thinking neutral safety switch for a 78 and newer model. My 77 was in the cab, but 78 in the engine bay right behind the carb when connected. Go to the trans and trace it up. My best guess is that it is either not connected or missing.
My 78 once drove through my garage wall...previous owner hotwired the NSS. I was tweaking the engine and instrument cluster, reached in to start it and it took off.
Both of my trucks are automatic trans.
My 78 once drove through my garage wall...previous owner hotwired the NSS. I was tweaking the engine and instrument cluster, reached in to start it and it took off.
Both of my trucks are automatic trans.
FTE Legend
Joined: Nov 2015
Posts: 30,870
Likes: 4,112
From: Angier, NC
I'm thinking neutral safety switch for a 78 and newer model. My 77 was in the cab, but 78 in the engine bay right behind the carb when connected. Go to the trans and trace it up. My best guess is that it is either not connected or missing.
My 78 once drove through my garage wall...previous owner hotwired the NSS. I was tweaking the engine and instrument cluster, reached in to start it and it took off.
My 78 once drove through my garage wall...previous owner hotwired the NSS. I was tweaking the engine and instrument cluster, reached in to start it and it took off.
Dave -----
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Tuned
Joined: Oct 2020
Posts: 260
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From: Lakeville, MN
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Lead Driver
Joined: Jul 2017
Posts: 9,578
Likes: 1,162
From: San Jose, CA
Not if you want your engine to start with the key.
The two red wires with blue traces, with the jumper on the other side of the connector, are from the ignition switch to the “S” post on the starter relay/solenoid.
What year is your truck? Sounds like a 78 or 79, so I’ll go with that for now. Or perhaps they changed in late 77, but you will definitely need to deal with many of those wires. looks like they would’ve normally been run over more to the driver side after exiting the firewall.
Funny, but your firewall looks to be an older truck. Maybe it’s just the fact that there’s no factory AC.
some of those other wires look to be important as well. Re w/green for the coil perhaps, along with the coolant temp, and oil pressure wires, maybe.
More pictures might be good, or describe the colors of the wires to us
The two red wires with blue traces, with the jumper on the other side of the connector, are from the ignition switch to the “S” post on the starter relay/solenoid.
What year is your truck? Sounds like a 78 or 79, so I’ll go with that for now. Or perhaps they changed in late 77, but you will definitely need to deal with many of those wires. looks like they would’ve normally been run over more to the driver side after exiting the firewall.
Funny, but your firewall looks to be an older truck. Maybe it’s just the fact that there’s no factory AC.
some of those other wires look to be important as well. Re w/green for the coil perhaps, along with the coolant temp, and oil pressure wires, maybe.
More pictures might be good, or describe the colors of the wires to us
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FTE Legend
Joined: Nov 2015
Posts: 30,870
Likes: 4,112
From: Angier, NC
Well there is that jumper you have to put back in place.
I would try my best to pull the wires apart so I could see where they go.
From the looks you only need to worry about the 2 wires with the jumper as the others do not look to be going to anything in the plug.
Unless that jumper has 3 wires going to it?
As bad as the wires are burned up you will have to pull them apart for tracing.
Dave ----
I would try my best to pull the wires apart so I could see where they go.
From the looks you only need to worry about the 2 wires with the jumper as the others do not look to be going to anything in the plug.
Unless that jumper has 3 wires going to it?
As bad as the wires are burned up you will have to pull them apart for tracing.
Dave ----
Cross-Country
Joined: Feb 2021
Posts: 64
Likes: 32
From: Fort Knox KY
Dude, I'd consider a total rewire. Not cheap, not hard but I'd also be worried about gremlins. I also had my harness fried but from the instrument cluster to the starter solenoid. American Autowire harness did me right and allowed me to remove several extra relays I'd added on. Again, not cheap but not hard to install.
Sure, you can fix that, wire by wire though. Id get the laminated wiring diagram from classic car wiring.
Sure, you can fix that, wire by wire though. Id get the laminated wiring diagram from classic car wiring.
FTE Legend
Joined: Nov 2015
Posts: 30,870
Likes: 4,112
From: Angier, NC
No one said it would be easy but you can see what strains go with a wire.
Use a knife to cut the melted cover but leave the strains till you get back to good wire.
Once back to good wire and you have a bunch of different color wire on hand cut 1 wire at a time, soider and heat srink it in place.
Do 1 wire at a time till all are replaced. For melted plugs do you really need them?
If so my NAPA has different number of wire pig tail plugs and use them in place.
Dave ----
Use a knife to cut the melted cover but leave the strains till you get back to good wire.
Once back to good wire and you have a bunch of different color wire on hand cut 1 wire at a time, soider and heat srink it in place.
Do 1 wire at a time till all are replaced. For melted plugs do you really need them?
If so my NAPA has different number of wire pig tail plugs and use them in place.
Dave ----
Lead Driver
Joined: Jul 2017
Posts: 9,578
Likes: 1,162
From: San Jose, CA
I believe a separate wire goes from the ignition switch to the ignition module. Same color, from the same position on the ignition switch, but separated from the starter relay wire.
The wire we can see in the pictures comes straight from the ignition switch, to that connector, through the jumper and back out the other one and onto the starter relay.
With an automatic transmission, the neutral safety switch is connected there with it’s four wires. Including two of the red with blue for the start function, and two with a black with red (I believe) for the backup lamps.
The jumper is used on manual transmissions, and the neutral safety switch is used on automatics.
The wire we can see in the pictures comes straight from the ignition switch, to that connector, through the jumper and back out the other one and onto the starter relay.
With an automatic transmission, the neutral safety switch is connected there with it’s four wires. Including two of the red with blue for the start function, and two with a black with red (I believe) for the backup lamps.
The jumper is used on manual transmissions, and the neutral safety switch is used on automatics.