Lead coil voltage reading question -- please help.
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87 NA build in progress
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Lead coil voltage reading question -- please help.
So trying to get this project wrapped up. The car will not start. We have no spark. I measure the power being put to the lead coil and it was 10.X volts. Measured it on my friend's working RX7 and he only had .13 V.
WHY???????
I'm thinking a grounding issue? Please give me a hand.
WHY???????
I'm thinking a grounding issue? Please give me a hand.
#2
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The black/yellow wire in the two socket, white connector should read batt voltage. If it does not, the ENGINE fuse might be blown in the interior fuse box. A less likely thing would be the Main Relay being bad. Not likely. And make sure both EGI fuse are good.
Last edited by HAILERS; 09-02-08 at 10:54 PM.
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Thats what I thought too Hailers, but the car that works reads a from the B/Y wire 0.13V when turned to the on position and 0.30V when cranking.
In my car, the non-working one, It reads 12.X at on and 9.X at cranking.
Why are the values different? Why does mine read so much higher? Could it be that a ground isn't working properly and I'm getting a surge?
In my car, the non-working one, It reads 12.X at on and 9.X at cranking.
Why are the values different? Why does mine read so much higher? Could it be that a ground isn't working properly and I'm getting a surge?
#4
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The black/yellow wire in the small, white, two socket connector should read batt voltage with the key ON, and when you have the starter turning, it should drop to about 9vdc like you see on one car. I've no idea why a car seeing itty bitty voltage on the black/yellow wire would even start.
It's like the dwg attached above. Key to ON.........causes power to go to the 15a ENGINE fuse in the dwg........which in turn powers the MAIN relay and Circuit Opening relays to pull in........which in turn causes power from the 40A EGI fuse to pass thru the Main Relay to the black/yellow wire that feeds the Lead and Trail coils.
Something is wrong here. Meter neg lead to a known gnd like the batt neg post and the pos to the black/yellow wire in the small, white, two socket connector at the lead coil. Key to ON and batt voltage should be there. Any small itty bitty voltage indicates the ENGINE fuse is bad or the Main relay isn't pulling in or the forty amp fuse is kaput......or battery cables are bad.
To me, your Working car shouldn't be......working and your non working car should be working. It's a mystery to me.
It's like the dwg attached above. Key to ON.........causes power to go to the 15a ENGINE fuse in the dwg........which in turn powers the MAIN relay and Circuit Opening relays to pull in........which in turn causes power from the 40A EGI fuse to pass thru the Main Relay to the black/yellow wire that feeds the Lead and Trail coils.
Something is wrong here. Meter neg lead to a known gnd like the batt neg post and the pos to the black/yellow wire in the small, white, two socket connector at the lead coil. Key to ON and batt voltage should be there. Any small itty bitty voltage indicates the ENGINE fuse is bad or the Main relay isn't pulling in or the forty amp fuse is kaput......or battery cables are bad.
To me, your Working car shouldn't be......working and your non working car should be working. It's a mystery to me.
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Tell me about it. I'm going to check Voltage output off of another car and I'll post the results. Hopefully, we should see a discrepancy. In which case the car that "should" work but isn't is missing grounds. Or....the car that is working shouldn't. Too much for my little brain to handle.
#6
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IF this is a rebuild then a ground problem could exist IF you didn't bolt down the ground ring on top of the rear rotor housing. It's the ground ring for the ECU. If that ground is missing, then it won't start. Starter will turn over, but no spark.
If this car has been running but now won't start, then it's unlikely that it is a gnd problem.
If this car has been running but now won't start, then it's unlikely that it is a gnd problem.
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