Fried ECU transistor

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Haulin
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Fried ECU transistor

Post by Haulin » Sun May 31, 2020 12:02 pm

I was driving and suddenly there was smoke coming from the center console. At first I thought that it's radio, but the smoke just kept coming and turned out that it's the ecu. It was really hot, but unplugging the wires and letting it cool, I did get back home without it getting hot again. Now the idle is pretty poor/no idle at all. Are these transistors related to fuel injector circuit? I saw a ecu pinout and it suggested that, it was for different year though. What could cause these burn? Car is 1994 2.0. If I get new ecu, does it matter if the serial number doesn't match? As long as it's in my case for 2.0, manual transmission and same year, it should be ok?


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Kit
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Re: Fried ECU transistor

Post by Kit » Sun May 31, 2020 4:37 pm

What’s the part No. on the ECU :?:
Is this what you need :?:
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Haulin
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Re: Fried ECU transistor

Post by Haulin » Sun May 31, 2020 5:34 pm

That is exactly same part number as mine. I have few local sources where to possibly get the ecu, if they don't work out, I get back to you. How much it would be shipped to Finland?

Kit
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Re: Fried ECU transistor

Post by Kit » Sun May 31, 2020 6:16 pm

What Finland :o
But yes,
If you give us a address/post-code , I’ll get a cost.
I’ll be surprised if you find one

Keep in touch

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Haulin
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Re: Fried ECU transistor

Post by Haulin » Mon Jun 01, 2020 2:27 pm

Did some measuring with multimeter. Turns out that burnt transistors middle leg is connected into IAC valve green/black wire.

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Re: Fried ECU transistor

Post by jrh » Mon Jun 01, 2020 3:52 pm

Best check that has a meaningful resistance and the solenoid is working properly , or else it will happen again.

Haulin
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Re: Fried ECU transistor

Post by Haulin » Tue Jun 02, 2020 10:02 am

What is the correct way to measure these valves? The one in the car was ~4.0 ohms, spare one in the picture below 14.5 ohms. Haynes manual says about 7.7-9.3 ohms.
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Re: Fried ECU transistor

Post by jrh » Tue Jun 02, 2020 1:20 pm

I would believe the reading of 14 ohms rather than the Haynes figure.
Almost certain it is the old IAC that killed your transistor.

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Re: Fried ECU transistor

Post by Haulin » Tue Jun 02, 2020 2:23 pm

Did check the spare one again and now it was ~10 ohms, so that seems to be ok. Now I have to decide if I want to hunt new transistor and replace it or just buy new ecu :D Would be shame tho to replace otherwise perfectly working ecu. Thanks to everyone who helped.

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Re: Fried ECU transistor

Post by Kit » Tue Jun 02, 2020 3:21 pm

You can have one of mine ECU’s, for the cost of the postage + a small donation to UKPOC funds ;) :)

Kit

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