under dash electrical

Recently replaced my steering column in my 90 model w/ one from an 87 model. After making all the connections, the circuit that controls radio, turn signals, and AC controls was dead. Jumped a wire from a constant hot on the fuse panel to the dead circuit just to verify it was a simple no power issue. A few moments later smelled something hot. Hot melted and burning peices of plastic started falling from the heater box by the passengers feet. Got it put out. The fire started just under the heating element inside the box. Why did this happen? If power is provided thru the column, is the voltage to the element reduced somewhere? Im stumped. Also, what is the yellow box behind the lower dash plate on the passenger side.Has several adjustment screws on it. One labeled sesitivity I think?

Devil_Mutt said:

Recently replaced my steering column in my 90 model w/ one from an 87 model. After making all the connections, the circuit that controls radio, turn signals, and AC controls was dead. Jumped a wire from a constant hot on the fuse panel to the dead circuit just to verify it was a simple no power issue. A few moments later smelled something hot. Hot melted and burning peices of plastic started falling from the heater box by the passengers feet. Got it put out. The fire started just under the heating element inside the box. Why did this happen? If power is provided thru the column, is the voltage to the element reduced somewhere? Im stumped. Also, what is the yellow box behind the lower dash plate on the passenger side.Has several adjustment screws on it. One labeled sesitivity I think?

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IIRC yellow box is the computer control for the cruise control. Good luck with the wiring problem, you need to get a set of 87 and 90 wiring diagrams, there were some changes in wire colors and different options affect the wiring too. I suspect you hot wired a ground wire or a shorted wire. Sounds like you might be describing the blower motor resistor pack (that you fried) that works with the blower speed switch to vary the blower motor speed on the A/C-Heat.

Have you checked all the fuses and fuses links? I had to bypass and rewire that same circuit on my 85 last year, but the problem(s) were on the back side of the fuse box and at the ignition switch and at the ignition switch wire and connector assy. Namely corrosion, shot and undersized wire and connectors. After burning up 2 ignition switches in 12 months I bypassed the ignition switch and fuse box and ran a new wire, 10 ga and installed a main power toggle switch for those accessories on the lower dash.

You should be able to find wiring diagrams at my RENIXPower group - groups.yahoo.com/group/RENIXPower. They're in the "Files" section in .pdf format.

Wow. Sounds like you jumpered something to the blower resistor/motor circuit since you said passenger foot area. You are going to have to trace the wires out.

yeah, I jumpered something all right

Any pictures of the remains?

Ecomike said:

Any pictures of the remains?

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damn! I'll bet you're that guy who just has to stop and stare at the accident on the side of the road too! It's bad enough that he's got a bar-b-que in his dash, but now you've got to slow down and gawk???? Just kiddin'-- pics would help us figure out what's been smoked.

--Shorty

Shorty said:

damn! I'll bet you're that guy who just has to stop and stare at the accident on the side of the road too! It's bad enough that he's got a bar-b-que in his dash, but now you've got to slow down and gawk???? Just kiddin'-- pics would help us figure out what's been smoked.

--Shorty

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:greensmok