Author Topic: Brake Light Confusion  (Read 13693 times)

Offline Boone83K10

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Re: Brake Light Confusion
« Reply #15 on: September 13, 2013, 09:21:01 AM »
does it unplug? or do I just probe it with a test light?
1966 Mercury Comet - Built 429 (First Car/Show Car)
1983 Chevrolet K10 - Built 350 (Winter Toy)
1992 Chevrolet Lumina Euro (Sold @ 265,000 miles)
2003 Ford Escape 4x4 - Mac Perf. Intake/Exhaust (Wifes' DD)
2007 Mercury Milan - Steeda Tuned (Summer Toy)

Online bd

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Re: Brake Light Confusion
« Reply #16 on: September 13, 2013, 10:42:12 AM »
Remove the retaining bolt from the center of the bulkhead connector, unplug the complete connector from the firewall socket, separate the rear lamp harness plug from the main body of the connector by sliding it sideways, then reconnect the main body of the bulkhead connector to the firewall - you have to reconnect the bulkhead connector to power the cab before testing.  Lay the rear lamp harness to the side and probe the firewall socket as you did at the rear of the vehicle.  If the results mimic those you attained before, the 'short' is in the under-dash wiring.

Checking the 'ground' at the rear of the bed should be performed using a voltmeter as Rich Weyand explained earlier.  Using a test light could be misleading.
Rich
It's difficult to know just how much you don't know until you know it.
In other words... if people learn by making mistakes, by now I should know just about everything!!!
87 R10 Silverado Fleetside 355 MPFI 700R4 3.42 Locker (aka Rusty, aka Mater)

Offline Boone83K10

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Re: Brake Light Confusion
« Reply #17 on: September 13, 2013, 12:25:05 PM »
sounds scary
1966 Mercury Comet - Built 429 (First Car/Show Car)
1983 Chevrolet K10 - Built 350 (Winter Toy)
1992 Chevrolet Lumina Euro (Sold @ 265,000 miles)
2003 Ford Escape 4x4 - Mac Perf. Intake/Exhaust (Wifes' DD)
2007 Mercury Milan - Steeda Tuned (Summer Toy)

Offline rich weyand

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Re: Brake Light Confusion
« Reply #18 on: September 13, 2013, 12:35:55 PM »

DISCONNECT THE BATTERY, then....

Remove the retaining bolt from the center of the bulkhead connector, unplug the complete connector from the firewall socket, separate the rear lamp harness plug from the main body of the connector by sliding it sideways, then reconnect the main body of the bulkhead connector to the firewall ...

then reconnect the battery and do your testing.

Reverse procedure to reinstall that portion of the plug.
Rich

"Working Girl": 1978 K-10 RCSB 350/TH350/NP203 +2/+3 Tuff Country lift

Offline Boone83K10

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Re: Brake Light Confusion
« Reply #19 on: September 13, 2013, 12:37:47 PM »
this?

1966 Mercury Comet - Built 429 (First Car/Show Car)
1983 Chevrolet K10 - Built 350 (Winter Toy)
1992 Chevrolet Lumina Euro (Sold @ 265,000 miles)
2003 Ford Escape 4x4 - Mac Perf. Intake/Exhaust (Wifes' DD)
2007 Mercury Milan - Steeda Tuned (Summer Toy)

Online bd

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Re: Brake Light Confusion
« Reply #20 on: September 13, 2013, 03:23:56 PM »
That's what it looks like.  But, you probably won't need to pry it apart.  It should separate fairly easily.  There's a foam gasket sandwiched between the connector and socket that may try to tear as you unplug it (a remnant of the gasket is pictured around the bolt), so take your time.
Rich
It's difficult to know just how much you don't know until you know it.
In other words... if people learn by making mistakes, by now I should know just about everything!!!
87 R10 Silverado Fleetside 355 MPFI 700R4 3.42 Locker (aka Rusty, aka Mater)

Offline Boone83K10

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Re: Brake Light Confusion
« Reply #21 on: September 14, 2013, 03:09:00 PM »
ok I took it off and tested at the firewall. All things are good. It is sending the correct signals through the firewall. So that means it is somewhere from there to the rear!

All the protective sheathing is in very good condition. I guess i will have to start somewhere. Could it be the rear plug possibly?
1966 Mercury Comet - Built 429 (First Car/Show Car)
1983 Chevrolet K10 - Built 350 (Winter Toy)
1992 Chevrolet Lumina Euro (Sold @ 265,000 miles)
2003 Ford Escape 4x4 - Mac Perf. Intake/Exhaust (Wifes' DD)
2007 Mercury Milan - Steeda Tuned (Summer Toy)

Offline rich weyand

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Re: Brake Light Confusion
« Reply #22 on: September 14, 2013, 03:40:26 PM »
plugs usually fail open, wires usually fail shorted.  you're shorted, so I'm betting on the harness.

Rich

"Working Girl": 1978 K-10 RCSB 350/TH350/NP203 +2/+3 Tuff Country lift

Offline Boone83K10

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Re: Brake Light Confusion
« Reply #23 on: September 14, 2013, 04:05:43 PM »

I began to pull the wiring off the frame rail... this is very bad. This truck has true dual exhaust from when it had the engine swap. They ran the driver pipe too close to the frame rail above the axle and it did this...







Now what do I do, anyone want to sell me the entire rear harness?? I don't feel up to running entirely new wiring from one end to the other.
« Last Edit: September 25, 2013, 09:46:47 PM by Captkaos »
1966 Mercury Comet - Built 429 (First Car/Show Car)
1983 Chevrolet K10 - Built 350 (Winter Toy)
1992 Chevrolet Lumina Euro (Sold @ 265,000 miles)
2003 Ford Escape 4x4 - Mac Perf. Intake/Exhaust (Wifes' DD)
2007 Mercury Milan - Steeda Tuned (Summer Toy)

Offline rich weyand

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Re: Brake Light Confusion
« Reply #24 on: September 14, 2013, 06:07:54 PM »
Just splice in a replacement.  Start up on the firewall, which is somewhat protected, about 18" off the connector.  Splice in a four-wire, direct-burial stranded cable.  Cover each solder joint with heat-shrink tubing, then coat the four splices in a bunch with silicone bathtub sealer.  Run the cable to the back, cut the factory splices off, and splice the cable to the existing wiring there the same way.

Here's something you can use.  Then you're not running separate wires, and they have more protection against water, oil, and gas.
http://www.amazon.com/WHITE-Increments-Speaker-Outdoor-Lighting/dp/B0091L60RG/ref=pd_sim_sbs_e_23
Rich

"Working Girl": 1978 K-10 RCSB 350/TH350/NP203 +2/+3 Tuff Country lift

Online bd

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Re: Brake Light Confusion
« Reply #25 on: September 14, 2013, 07:43:05 PM »
If the only damage is over the rear axle then repair that section.  Or, string new cable from the front of the bed to the rear harness plug.  Clean the copper strands of the old wires thoroughly so solder can adhere.  Using uninsulated tinned copper butt splices, crimp, solder and heat-shrink the old wires to the new wires then tape it up.  Use double wall, self-sealing, heat shrink tubing to seal the connections from water and dirt.

As you run the cable to the rear be sure to route it further from the exhaust and clamp it in place with Adele clamps.  For extra protection, you can procure some Syn-flex air line of the appropriate inside diameter and use that for conduit.
Rich
It's difficult to know just how much you don't know until you know it.
In other words... if people learn by making mistakes, by now I should know just about everything!!!
87 R10 Silverado Fleetside 355 MPFI 700R4 3.42 Locker (aka Rusty, aka Mater)

Offline Boone83K10

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Re: Brake Light Confusion
« Reply #26 on: September 14, 2013, 07:44:31 PM »
Actually, I think I will just purchase and install a complete new rear wire harness rather than patch the old one.
« Last Edit: September 14, 2013, 09:04:59 PM by bd »
1966 Mercury Comet - Built 429 (First Car/Show Car)
1983 Chevrolet K10 - Built 350 (Winter Toy)
1992 Chevrolet Lumina Euro (Sold @ 265,000 miles)
2003 Ford Escape 4x4 - Mac Perf. Intake/Exhaust (Wifes' DD)
2007 Mercury Milan - Steeda Tuned (Summer Toy)

Offline Boone83K10

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Re: Brake Light Confusion
« Reply #27 on: September 14, 2013, 09:22:57 PM »
my bad?
1966 Mercury Comet - Built 429 (First Car/Show Car)
1983 Chevrolet K10 - Built 350 (Winter Toy)
1992 Chevrolet Lumina Euro (Sold @ 265,000 miles)
2003 Ford Escape 4x4 - Mac Perf. Intake/Exhaust (Wifes' DD)
2007 Mercury Milan - Steeda Tuned (Summer Toy)

Online bd

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Re: Brake Light Confusion
« Reply #28 on: September 14, 2013, 09:36:59 PM »
Even with a brand new harness, you'll need to take precautions against frying the new one! 


If you're determined to install a new harness, have you checked with the store here?  You can email or PM Captkaos for availability and price.
Rich
It's difficult to know just how much you don't know until you know it.
In other words... if people learn by making mistakes, by now I should know just about everything!!!
87 R10 Silverado Fleetside 355 MPFI 700R4 3.42 Locker (aka Rusty, aka Mater)

Offline Irish_Alley

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Re: Brake Light Confusion
« Reply #29 on: September 14, 2013, 11:05:55 PM »
either way will work one will just cost more money and you would still have to figure out how to run the wires to keep them away from the heat.
« Last Edit: September 25, 2013, 09:47:45 PM by Captkaos »
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