Ive got a fun one for all of you lads. I was driving the other day, put the car in park and a nice white cloud of electrical smoke came from under thr dash. The car stopped and refused to restart.

i checked all the fuses and theyre intact. The car turned over but wouldnt start - no power to the distributor. I needed to get home so i ran a wire from the battery + to the dist and drove home. I have no power to the instrument panel - no tach, no volts and no temp. Turns out i also have no indicators.

all of my accessories work, even the air con!

my cars background is colourful. Was an 87 with an e4me, now back to a mechanical quadrajet and a vac advance dist.

is there a magical wire in the dash somewhere that powers the dash instruments. And would this explain the indicators not working.

told you this would be fun

 

Studying the wiring diagram ive noticed a couple of things that could help.

Indicators/Turn Signals

• The hazards are still working, which means that there is still power going through the Hazard Flasher Unit. ill check out the normal flasher unit this afternoon.
  
• The diagram is slightly complicated. Power to the flasher is provided by a hot-in-run DARK BLUE wire. the fact that the hazards kick the lights on means there is likely nothing wrong with the wiring to the lights themselves and more than likely exists on this dark blue line, or the line that feeds it - Being a hot-in-run feed, this points at the ignition circuit.

Gauges

• The only clue about what powers the gauges that i have is a wiring diagram that says the ECM (which is actually still in the car) is powered by a hot at all times ORANGE wire, and there is a TAN/BLK wire that runs to the instrument cluster.

Distributor Power

The strangest one of all of them. As this was previously a ECM controlled car with a CC distrbutor and CC Carb, i utilized the existing switchable PINK power wire that powered the original distributor. This line is dead now - hence hotwiring the distributor from the battery to get me home.

The wiring diagram tells me that this power goes back to the ignition switch itself, but not the route on how it gets there.


EDIT - Oddly enough now that ive looked at a different diagram, the PINK wire powers the distributor, gauges and also the ECM.

Does anyone have any ideas if these are powered off of a fusible link?

 

Your electrical power starts at the battery and then runs thru a couple of heavy gauge ( red ) wires and into the car thru the C100 Firewall connector. These heavy gauge power wires have Fusible links on them near the starter and those fuseible links should be checked to be sure they are good. You can probe the C100 connector red wires at Pins 'A4' and 'G5' of your 87 to ensure that they are getting full time power thru the fusible link.

Here is the C100 diagram for your 87....



From there;

Power from the 'G5' terminal of C100 leads directly to the Light Switch & the ACC fuse.

Power from the 'A4' terminal leads to the Ignition switch, the 'Power Accessory circuit breaker', and the Fuel Pump / Fan fuse on the fusebox.

Power to the distributor comes from the Ignition switch and then leads back thru C100 at pin 'F4' ( PINK wire ). This same circuit also sends power to the ignition coil, the 'Engine Control' fuse, the 'Turn/Back-up' fuse and the 'Gauges' fuse.


The 35AMP circuit breaker and Fuel Pump/Fan fuses in the fuse box should have power at all times ( thru F4 of C100 ) if the fusible link is OK. If these circuits HAVE power at all times than the fusible links are probably good. ( You can also probe the 2 RED wires @ the Ignition box to check for 'hot at all times' power as well - they are on the same circuit. )

If you have power at all times on those red wires at the ignition switch than probe the PINK wire at the ignition switch while the key is in RUN, BULB TEST or START for voltage; If there's no voltage on that pink wire ( in RUN, Bulb Test, or Start ) than the problem is the ignition switch.

Here are a couple diagrams of the 1985 Carb power wiring. it should be very similar ( if not exactly ) the same as your 87 wiring. These should help explain what I'm describing,... because a picture sure IS worth a thousand words !!!!







With any luck you will quickly find the problem, Probably a bad fusible link or - most likely - a bad Ignition Switch.

Good Luck !