Engine harness short?
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Engine harness short?
I know the answer to this may seem obvious, but before I tear the entire engine harness out I figured I'd ask.
I've been doing a lot of wiring in the car lately with the new ignition system. Well, when I went to test, I was unable to start the car. My battery was drained. So I charged it and tried again, still nothing.
In an attempt to diagnose, I disconnected the megasquirt ECM and removed the battery. Then I checked continuity between the two battery terminals. I have continuity. I checked resistance, 55k ohms.
Is this a good indication of a short in the harness somewhere?
I've been doing a lot of wiring in the car lately with the new ignition system. Well, when I went to test, I was unable to start the car. My battery was drained. So I charged it and tried again, still nothing.
In an attempt to diagnose, I disconnected the megasquirt ECM and removed the battery. Then I checked continuity between the two battery terminals. I have continuity. I checked resistance, 55k ohms.
Is this a good indication of a short in the harness somewhere?
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Little update, with key on I go from 55,000 ohms resistance to 4 ohms resistance.
So my short is definitely somewhere that receives power at key on. I've eliminated the alterenator, starter and ecm power and ignition power lines.
Still hunting...
So my short is definitely somewhere that receives power at key on. I've eliminated the alterenator, starter and ecm power and ignition power lines.
Still hunting...
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3 fuses under the hood have shorts run through them. I'm trying to figure out what these fuses are for but they are not labeled. :(
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Oh I found it! I pulled the C100 firewall harness off. I found ground on a large yellow wire. Yellow is switched 12V ignition. I traced it back to the transmission for the neutral safety switch and disconnected it there. No more ground at the C100 so I kept going. Also on the NSS the purple wire had ground. Took the purple wire off of the NSS runs to the starter signal. So I checked it at the starter and sure enough, ground. So just to make sure, I pulled the start wire off of the solenoid and... you guessed it ground at the solenoid.
I just bought this FU#@%NG starter last year and it has maybe 100 starts on it because I took the car off the road for the engine swap and then it sat all winter.
Im going to raise some hell, as soon as I remember where I bought the starter.
I just bought this FU#@%NG starter last year and it has maybe 100 starts on it because I took the car off the road for the engine swap and then it sat all winter.
Im going to raise some hell, as soon as I remember where I bought the starter.
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#7
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You sure there'* a short? maybe it'* just an uncompleted circuit? That'* along the same lines as testing a light bulb that doens't work and saying.. it'* got a short. The filament is supposed to short.
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When I measured across the battery terminals (with the battery removed), I had continuity. So yea I'm sure it was a short. The resistance across the terminals went from 55k ohms (still a short) with key off to 4 ohms (very bad short) at key on. That lead me to the C100 firewall connector where I found that the switched 12V line had ground on it.
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