Electrical, rad fan runs on start, blows Rt hd lamp fuse

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Kurt
Prelude Enthusiast
Posts: 2
Joined: Fri Aug 12, 2011 9:26 am

Electrical, rad fan runs on start, blows Rt hd lamp fuse

Post by Kurt »

Hi,
I hope someone can direct me where to test next.

93 S model 2.3 has been perfect up to 168k miles. Turned the key, heard a small snap under the dash and now it does all of the following:

Neutral safety switch will not function. replaced brake switch. no change. no power to plunger solenoid that releases A/T shift lever.
Blows right head light if fuse on replaced (when running)
Blows horn fuse when running. Horn stays on when fuse replaced but not running.
Brights indicator on dash flutter when headlights turned on and running, brights flutter to match.
Radiator fan comes on at turn of key to run position. never did before.
cruise control does not function.
removed horn relay and started car, no change. reinstalled.
battery shows 13.8-14 volts at idle warming up. seems normal.

No warning lights on dash. still runs great.
Electrical wiring is in great shape, can has been driven summers only.
Alternator has 40k miles and seems normal

MAIN Relay, ECM?

I looked at the wiring guides for common points and looked on the forums I see no similar issues.

Please help! Thank you.

Kurt

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spiffyguido
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Joined: Fri Nov 11, 2005 2:55 am
Prelude Model: 1991 SE-SR
Location: Alberta, Canada
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Re: Electrical, rad fan runs on start, blows Rt hd lamp fuse

Post by spiffyguido »

Hi Kurt,

Welcome to the forums.

It sounds to me like you have a pretty bad short somewhere in your electrical system. These are almost always very difficult to find, but with some work, you'll be able to resolve the issue.

It's probably going to be easiest to troubleshoot this by starting with just one circuit and seeing if you can find the short. Since it's a relatively short circuit, the neutral safety switch seems like a good first pick. Trace the wires in this circuit and see if you can find any breaks or tears that are causing them to short. Because the symptoms are so wide spread, I'm going to predict that a wire has shorted to the body of the car somewhere.

The small 'snap' sound you heard when everything started going wrong may provide a clue. I'd get your head under the dash with a flashlight and dig around to see if you can see any wires that have frayed and are now shorting to the firewall.

Kurt
Prelude Enthusiast
Posts: 2
Joined: Fri Aug 12, 2011 9:26 am

Re: Electrical, rad fan runs on start, blows Rt hd lamp fuse

Post by Kurt »

ok will do.



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