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PCM relay keeps blowing

Old 11-24-2018, 07:38 PM
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Join Date: Nov 2018
Location: Missouri
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Default PCM relay keeps blowing

I was driving down the road and my car suddenly dies and so I pull over and I notice my theft light is blinking on and off and I try rolling it over and it acts like it wants to start but it doesn’t and so I look on a few YouTube videos and I go to look under the hood and pop the fuse box and start pulling fuses and I see that my pcm fuse is burnt out and so I go to put another fuse in and it blows as well and it keeps blowing each fuse I put back in it. I drive a 1997 Mustang GT
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Old 11-25-2018, 02:20 PM
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Location: Pennsylvania
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Your title says the RELAY keeps blowing, then your detail says FUSE...

Check the the noise suppressor on the back of the driver side head. If it is shorted,
it will keep blowing the ECM fuse.

Shorting fuel injectors could cause it, or aftermarket injectors that want more current.

Check for a shorted wire to the data link connector (OBD port).

Shorted O2 Sensors...

It is a short, for sure, so you have to find it. Most of the time, it is the ECU, internal.
You'd need tons of fuses to test circuits that go to the ECU harness, to unplug them
one at a time to test...
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Old 11-25-2018, 09:37 PM
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Are you sure it is a FORUM issue?

Forum Issues and Feedback Discuss any issues you are having with using Mustang Forums here.
Please look at the section that you are posting in. This is not the section for your car, as the title and explanation at the top say, it is for problems with using the Forum.
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Old 01-06-2019, 08:48 PM
is my username.
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Two months later, I move tech....****
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Old 01-06-2019, 09:04 PM
Urambo Tauro
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Definitely sounds like a short. Hope you managed to find the source by now.
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