78 C10 Bonanza Cargo Light

[donald_b_bell]

My 1978 C10 Bonanza had a previous owner place a camper shell on the bed. The OEM Cargo Light did not fit with the camper shell, so it was removed and discarded. The wires were cut and the hole was closed with a piece of aluminum. I bought a new cargo light assembly and a wiring harness from LMC. The wiring harness includes about four feet of wire with numerous connectors. There are two single conductor connectors on the orange wire. There is a large two conductor connector (white and orange) near the end, then there are two single conductor connectors at the very end (one on white and one on orange).

Where does this connect inside the truck and what is to be done with all of the connectors? How do you manage to snake all of this wire back down the passageway between the outside of the cab and the inside of the cab? My truck does not have a headliner.

[Ziegelsteinfaust]

My truck has a sliding switch for the cargo light, but it doesn't work.

You could use a piece of long wire to fish down roof section to where you can htab it out the bottom

[donald_b_bell]

Where is the sliding switch located? I have not noticed a sliding switch on my truck. I have not had it long and do not have a good knowledge of where everything is located. I am a bit confused on how to turn the cargo light on.

Where does the wiring harness come out at the bottom? I know that it must go around the window, but does it come out behind the seat?

[TexasJeff]

The cargo light switch is normally on the dash next to the ash tray and if you have them the dual fuel tank switch. The cargo light circuit ties into the dome light circuit, some how, I don't have my schematics here at work but I can check when I get home.

[KrazyRay]

The switch should be located by the driver side shoulder seat belt. The wires connect to the inside dome light wiring at the B pillar.

[donald_b_bell]

My situation was that the Previous Owner had removed the cargo light because it was not compatible with the camper shell that he had on the truck. The cargo light had been discarded and the wiring harness was cut out at the back of the cab where the light mounts. Yesterday, I tacked the project and replaced the wiring harness and mounted the new cargo light.

I removed the slide switch and disconnected the two orange wires that make up the switch leg. I tied a string onto the remaining wire at the back of the cab. I pulled the old wiring harness from the switch hole until the string appeared. Then, I continued to pull the old harness from behind the seat at the B Pillar.

I taped up the connectors on the new harness and pulled it through using the string. It was difficult to make the turn at the top of the cab, but with a little poking from a fish tape through the hole at the back of the cab, I finally made it around the turn and back to the switch hole. I pulled everything through to the switch hole, pulled the two orange wires through, and then continued on down the B Pillar with the rest.

I found that the new wiring harness was identical in length to the old one. Everything fit up perfectly.

When I disconnected the old harness from behind the seat, I broke an attachment point for the connector to the body. This physical connection keeps the wire from swinging like a pendulum while you drive and causing annoying rattles. I plan to correct this by putting a small wire tie through the hole where the OEM connector was attached.

I purchased both the cargo light and the wiring harness from LMC. I found both to be excellent in quality. However, there was a strange thing about the cargo light. It came with the plastic lens assembled to the body. The two screws that secure the lens to the body were both assembled using Loctite or some other type of glue. It was almost impossible to remove these screws! I did some damage to the Phillips head of the screws in removing them. I had no choice but to remove them because you cannot mount the cargo light with the lens in place.

I did this by myself and the job took a few hours. Most of this was dedicated to pulling the new wiring harness through the cab roof. I did some damage to the cardboard box behind the seat as it is 36 years old and a bit brittle. I also found that the slide switch, which had not been used in years, has to be jiggled to get the light to turn on. I may choose to replace that too, but it will probably free up with some use after I knock out the dust.

I highly recommend the parts from LMC. The part number for the Cargo Light assembly is 36-4498 and the part number for the wiring harness is 36-3252. Both were available "In Stock" for $30 each. I have no idea why they would assemble the lens with Loctite on the screws, but this was a major pain. I am in search of some replacement screws (these are special shoulder screws) to perfect the job. Right now, the ones with damaged heads are holding.