No headlights, taillights, gauge lights or radio power in 1989 Convertible (added fuse block photos)

[JensenHealey]

Took a battery over to the shop where the 1989 Convertible is located and tried various things to see what condition the electrical system is in.

Things that work:

• starter
• gauges
• hazard lights & turnsignals
• brake lights
• power windows
• power top motor (I can hear when working the switch but I don't know if it actually raises or lowers the top)

 

Things that don't work

• headlights
• taillights
• gauge lights
• trunk release
• gas lid release
• power seats

When I checked the fuse box I found three missing 20A fuses, one of which was marked as taillights. I replaced these three fuses and I checked to see if the electrical contacts behind the fuses each had power. The only one that did not have power to the contacts inside the fuse block was the taillight fuse.

I went over there hoping to get the trunk open on the car but pressing the trunk release button or the gas lid release button inside the center console did nothing. No click noises or anything.

 

I did notice that wired into the harness around the fuse block was a "Tec-M headlight delay module" so I suppose that could be the cause of the lack of power to the headlights & taillights. It uses a lot of those awful vampire taps to hook onto the harness so I never been wild about that type of wiring "solution"

Edited January 11, 2021 by JensenHealey

[studegary]

With the amount of rust shown on one Avanti, and assuming the other is about the same, I expect that you will have a lot of electrical problems due to bad grounds.  

[JensenHealey]

Actually the 1989 convertible was stored indoors so it much cleaner than the wrecked blue convertible.

The strange thing is so far all of the electrical items I have checked on the wrecked blue car all work, lights, trunk release and power seats, so it seems like electrically the wrecked car that was stored outdoors is in better condition than the unwrecked white 1989 convertible that was stored indoors.

Later today I will go back over to that other shop and take some photos of that Tec-M headlight delay module and all of the vampire taps in the wiring harness around it. I am tempted to try removing this thing to see if it makes any difference with the non-working items in the electrical system.

Edited November 28, 2020 by JensenHealey

[wdaly]

I'm wondering if you should simply cut-off the Tec-M wires first to see what happens (maybe the unit is bad).  Removing those wire 'taps' could possibly make the original wiring problematic.

[JensenHealey]

Here are some photos of the under dash wiring and a closeup of the fuse box itself on the 1989 convertible car where the headlights, taillights, dash or gauge lights and a few other things do not function. For a complete list of functioning versus non-functioning items see the first post in this thread.
If anyone would like to see them I have fullsize 4K resolution files for these.
As I have said before there is no power to the fuse socket that is marked "taillights". I do not see a corresponding circuit or fuse for the power to the headlights or a fuse for the dash lights.

Edited January 11, 2021 by JensenHealey

[brad]

There is a s\connector hanging down in your next to last pic. The white plastic with the black locked connector is the dimmer switch. It should be mounted to the steering column and a rod from the turn signal stalk activates it. There is a dash light and gauge harness it has a large screw together connector located just at  the upper edge of the drivers side console between the dash cross brace and the edge of the dash. I have the complete wiring diagrams for 87-89 cars.

[JensenHealey]

Yeah, I am aware that that dimmer switch is hanging loose. The guy I bought the car from had no keys to the car when he got it and he disassembled the steering column and steering wheel in an effort to unlock the column so he could move the car. As a result a lot of stuff is screwed up or lost inside the steering column around the horn button and turnsignal cancelling mechanism.

 

BTW, your website appears to be a single dead page with no links.

Edited January 11, 2021 by JensenHealey

[IndyJimW]

My 87 Coupe has 3 wires supplying power to the fuse block, sounds like one of them is dead. Check at the firewall plug connector, for power on both sides.

Good luck,

Jim Wood

[JensenHealey]

Would it be possible to post a photo of this firewall plug so I know what I am looking for?

Thanks

[IndyJimW]

On your 88 it would be between the wiper motor and the wiper fluid tank. But from pictures of another 89 it looks like they changed it. They may have used the Caprice firewall plug. It would be two piece with a bolt in the center that clamps the outer and inner pug connectors together through the firewall.

Good luck,

Jim Wood