3rd brake light/cargo light function
3rd brake light/cargo light function
Hey guys. My Base model F-150 came with the one-piece all red CHMSL w/o the cargo light function. I stopped by the junk yard yesterday and found a totallted F-150 XLT with one and I popped it off, cut the wires, and bought 3x new bulbs for it since the old ones were pretty burnt up. I installed it but noticed when I open the door, the two cargo lights light up and the brake light. If I step on the brake, then the brake light shuts off and only the 2 cargo lights are one. There are no problems when I'm driving, the brake light works normally. I'm just wondering:
Is the brake light supposed to come on when the cargo lights do? If not, could the problem be a miscrossed wire? There was 1 green and 2 black wires, I may have miscrossed the two black ones.
Thx.
Is the brake light supposed to come on when the cargo lights do? If not, could the problem be a miscrossed wire? There was 1 green and 2 black wires, I may have miscrossed the two black ones.
Thx.
Senior Member
Joined: Sep 2007
Posts: 500
Likes: 1
From: La Porte, TX
Well, looking at the Chiltons at what little I can get from it, your wiring is right.
The blue/black wires go right to the cargo lamps and the light green goes right to the CHMSL.
The only things in the way in between the lights and the junction box are the brake pedal position switch and the interior lamps relay.
One of those parts has to be different between models with and without cargo lamps. The interior relay, I guess.
If someone out there has a factory wiring diagram, by all means chime in...
The blue/black wires go right to the cargo lamps and the light green goes right to the CHMSL.
The only things in the way in between the lights and the junction box are the brake pedal position switch and the interior lamps relay.
One of those parts has to be different between models with and without cargo lamps. The interior relay, I guess.
If someone out there has a factory wiring diagram, by all means chime in...
Technical Article Contributor
Joined: Jun 2002
Posts: 10,511
Likes: 10
From: Under the flightpath of old ORD 22R
As AlfredB18 posted, the interior lamp circuit is the Black w/ Blue stripe wire ( circuit 53 ) is for the cargo lamps themselves. This would have those 2 bulbs on with the interior lamps. The ground for it i one of the black wires.
The CHMSL is the Light green & Black wire ( light green is the power from the brake pedal position switch circuit 511 ).
The the EVTM page 90-3 below, you can see the connector C203, this is in the pass side kick panel, directly below the A-pillar on the passenger side.
I don't have access to my DVD right now, but the 2001 paper copy of the EVTM has connector C900 ( instead of C416 ) this is in the headliner to the pass side of the opening. you might have to drop the headliner to find it ( might not be close enough to the opening for the CHMSL lens ).
The connector to the lens itself is marked as C912.
You will need to pull the coat hanger on the passenger side, and remove the C-pillar trim panel, to pull down the head liner, to see if the connector is back there. If not, you will need to find an interior lamp circuit, or run a new circuit if you want to put it on a separate switch ( vs. the factory operation of running with the interior lamps ).
Take a look for the connector in the headliner, to see if you find the Black w/ Blue stripe wire in the connector ( should be the same direction as the CHMSL wires, they take the same path ).
good luck
1992 EVTM 90-3
The CHMSL is the Light green & Black wire ( light green is the power from the brake pedal position switch circuit 511 ).
The the EVTM page 90-3 below, you can see the connector C203, this is in the pass side kick panel, directly below the A-pillar on the passenger side.
I don't have access to my DVD right now, but the 2001 paper copy of the EVTM has connector C900 ( instead of C416 ) this is in the headliner to the pass side of the opening. you might have to drop the headliner to find it ( might not be close enough to the opening for the CHMSL lens ).
The connector to the lens itself is marked as C912.
You will need to pull the coat hanger on the passenger side, and remove the C-pillar trim panel, to pull down the head liner, to see if the connector is back there. If not, you will need to find an interior lamp circuit, or run a new circuit if you want to put it on a separate switch ( vs. the factory operation of running with the interior lamps ).
Take a look for the connector in the headliner, to see if you find the Black w/ Blue stripe wire in the connector ( should be the same direction as the CHMSL wires, they take the same path ).
good luck
1992 EVTM 90-3
Okay, nvm. I'll live with the brake light coming on.
Question though: I am upgrading to an all LED CHMSL soon and I've been debating getting one with red LEDs for the center stop and white LEDs for the white cargo lamp, but then again, I was thinking:
A.) i have this little problem here and,
B.) I'll be getting a tonneau soon and I plan to run two strips of LEDs under the rails to provide bed lighting, so:
do you think I should get these (CHMSL & Cargo Light Function)
or these (all 3 CHMSL):
Question though: I am upgrading to an all LED CHMSL soon and I've been debating getting one with red LEDs for the center stop and white LEDs for the white cargo lamp, but then again, I was thinking:
A.) i have this little problem here and,
B.) I'll be getting a tonneau soon and I plan to run two strips of LEDs under the rails to provide bed lighting, so:
do you think I should get these (CHMSL & Cargo Light Function)
or these (all 3 CHMSL):