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Khajjathefang
07-20-2011, 11:46 PM
I recently bought a project Shelby Z and I'm trying to get it started. When the key is turned I noticed the tach jerk but there are no lights on the dash whatsoever. electrical accessories such as the seat and starter motor work but the fuel pump seems to be DOA. even tried the positive to the coil post trick and had no response. eyeballed the fuses and they all look intact. So right now I'm thinking Dead computer? Luckily I have another Shelby Z I can grab some things out of but If that doesnt work I'd appreciate any suggestions<br>

let me clarify, there are no idiot lights when ignition is on. nothing from the dash whatsoever.

cordes
07-21-2011, 01:13 AM
Test for voltage at the pump while jumping it from the battery to the coil. If there is none, it's an electrical issue. If there is, dead pump.

turbovanmanČ
07-21-2011, 02:55 AM
Test for voltage at the pump while jumping it from the battery to the coil. If there is none, it's an electrical issue. If there is, dead pump.

I'd say wiring issue would be more accurate, :p

Khajjathefang
07-21-2011, 07:17 AM
What about the dash? The auto door belts don't move either, though I'm not sure about what criteria is required to activate them

Force Fed Mopar
07-21-2011, 07:28 AM
Try unplugging it and plugging it back up :) Could also be a fusible link. Or a power module.

cordes
07-21-2011, 12:54 PM
What about the dash? The auto door belts don't move either, though I'm not sure about what criteria is required to activate them

If nothing works except for the starter, I would check the ignition switch first and go from there. I had one fail intermitantly on me for a while and I spend months chasing it due to the fact that I had changed out my heater core at the same time and thought I broke a ground in there somehow.

Khajjathefang
07-21-2011, 06:30 PM
In the few minutes I had between work and class I pulled the stock LM in favor of the known good one from my parts car. more of a key on twitch from the gauges, headlights worked, key chime, still no door belts, idiot lights, or fuel pump. Gonna try a spare gauge cluster next, see if we can get diagnostics running.

Cordes, I assume I will have to remove the pump to check voltage? that might have to wait till I have the 255 out of the old one :lol:

cordes
07-22-2011, 12:22 AM
In the few minutes I had between work and class I pulled the stock LM in favor of the known good one from my parts car. more of a key on twitch from the gauges, headlights worked, key chime, still no door belts, idiot lights, or fuel pump. Gonna try a spare gauge cluster next, see if we can get diagnostics running.

Cordes, I assume I will have to remove the pump to check voltage? that might have to wait till I have the 255 out of the old one :lol:

No, just remove the plug from the pump and test for voltage at the plug. If it's not getting to the pump from there it's most likely a burnt out pump that fried the wires in the tank.

Khajjathefang
07-22-2011, 12:46 AM
Alright, cool. hopefully I can hit that sunday

Khajjathefang
07-23-2011, 02:43 PM
Thanks for the tip cordes, no juice at the plug. It is the three wire one correct? checked both the green and the white wire and got nothing. I think I'll go back again and check them against vehicle ground instead of just the wire

Khajjathefang
07-23-2011, 02:56 PM
oops looks like i had the sending unit plug. solid 12v at the two wire plug. Ill have to see if i can dig up my old working junk pump before i pull the 255.

Thanks guys. now i gotta figure out whats up with the dash lights :P

cordes
07-24-2011, 04:12 PM
Glad to hear that you have figured out one aspect of it.