Electrical Troubleshooting
#1
Electrical Troubleshooting
Good weekend folks. first things first i have a 93 running an MS3Pro. i did a complete engine rebuild, turbo system upgrade, and chassis refresh on the car. i've gotten to the point where everything is back together except the interior. i got myself a fresh uncut harness from a clean car at the junkyard. here's my problem.
condition: key at "ACC" and all accessories (radio, cigarette lighter) are getting 12V
condition: key at "ON" MS3 lights 1 and 4 are illuminated, no prime to fuel pump, WHT-RED wire (ignition power) has 3.5V, circuit opening relay is not activating (no power on VIO wire {should be getting power from MS3}) therefore not actuating the relay and priming the fuel pump. LT-GRN wire at circuit opening relay has 3.5V
condition: key at "START" no changes to key at "ON"
ive swung tested a known working circuit opening relay and had the same results. where else should i be looking as far as relays or power supply? why isn't there enough juice flowing at "ON?" any help is appreciated.
EDIT: wiring harness is from a 92, and the only difference i've encountered was one of the plugs that feeds the chassis harness (to the fuel pump stuff) had to be repinned. continuity was checked on all wires to verify it was repinned correctly.
condition: key at "ACC" and all accessories (radio, cigarette lighter) are getting 12V
condition: key at "ON" MS3 lights 1 and 4 are illuminated, no prime to fuel pump, WHT-RED wire (ignition power) has 3.5V, circuit opening relay is not activating (no power on VIO wire {should be getting power from MS3}) therefore not actuating the relay and priming the fuel pump. LT-GRN wire at circuit opening relay has 3.5V
condition: key at "START" no changes to key at "ON"
ive swung tested a known working circuit opening relay and had the same results. where else should i be looking as far as relays or power supply? why isn't there enough juice flowing at "ON?" any help is appreciated.
EDIT: wiring harness is from a 92, and the only difference i've encountered was one of the plugs that feeds the chassis harness (to the fuel pump stuff) had to be repinned. continuity was checked on all wires to verify it was repinned correctly.
#4
Tweaking Enginerd
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Swapping the harness is a big touch. The low voltage on R/W is your smoking gun, stay on that. Confirm that R/W isn't shorted to ground, the tried a different relay with the same results step has derailed many. You can bypass the relay with a jumper to see if you get 12V on R/W. Download the wiring diagram and study it carefully.
#5
Swapping the harness is a big touch. The low voltage on R/W is your smoking gun, stay on that. Confirm that R/W isn't shorted to ground, the tried a different relay with the same results step has derailed many. You can bypass the relay with a jumper to see if you get 12V on R/W. Download the wiring diagram and study it carefully.
#6
Swapping the harness is a big touch. The low voltage on R/W is your smoking gun, stay on that. Confirm that R/W isn't shorted to ground, the tried a different relay with the same results step has derailed many. You can bypass the relay with a jumper to see if you get 12V on R/W. Download the wiring diagram and study it carefully.
#7
Swapping the harness is a big touch. The low voltage on R/W is your smoking gun, stay on that. Confirm that R/W isn't shorted to ground, the tried a different relay with the same results step has derailed many. You can bypass the relay with a jumper to see if you get 12V on R/W. Download the wiring diagram and study it carefully.
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