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Unread 03-29-2010, 04:39 PM   #16
lexinator02
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I was contemplating that but the copper connections also look burnt up so even if I put a new resistor in I dont know if the connections work. I ordered a refurbished one for 110 from rock auto.. Im just afraid whatever that resistor controls isnt fixed so when I plug in the new ecu it will fry again...

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Unread 03-29-2010, 05:07 PM   #17
Que89YJ
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Ok. I can help you there. Use a multimeter and put in on ohms. Touch one lead to the leg of the resistor closest to the connector and then one by one touch the pins on the front of the connector until you find the one that reads 0 ohms. Tell me what pin that is. It looks like a load resistor for a high current load but in the renix controller there should be any. They used relays and the solinois for all the high currents unless its the ignition feed. Yes, you should double check on what circuit it is. You might have a short. The fuses are designed for protecting the wires in the vehicles not the electronics so you could possibly blow another controller by hooking it back up without knowing for sure your ok.
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Unread 03-29-2010, 05:10 PM   #18
laybackman
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Quote:
Originally Posted by lexinator02 View Post
I was contemplating that but the copper connections also look burnt up so even if I put a new resistor in I dont know if the connections work. I ordered a refurbished one for 110 from rock auto.. Im just afraid whatever that resistor controls isnt fixed so when I plug in the new ecu it will fry again...
A buck ten for a refurbed unit isn't bad at all and saves you time. Do you have to send them your old unit or pay a core charge if you don't?
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Unread 03-29-2010, 05:12 PM   #19
lexinator02
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I have my multimeter at the office so I cant check til tomorrow. So basically touch each pin individually while touching the leg of the resistor? Do I touch the near or far side of the resistor? I think if I find what pin it is, I can double check the wiring atleast. I kind of eye balled it and it looked like pin 6 which is the fuel pump relay which would explain why even though it had power, the relay wasnt clicking.


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Unread 03-30-2010, 04:53 AM   #20
Que89YJ
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It should be the side closest to the header/pins. I am surprised if its the fuel pump relay. That is low current. It's just used to control power.
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Unread 03-30-2010, 06:38 AM   #21
lexinator02
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Well I took some measurements and there were 2 pins with low readings. The rest were high.

Pin 16- (5.0volt supply to map and TPS sensor) read .2, this was also the only one to read 0 ohms and beep.

Pin 19- (system power B+) read 1.08

Not entirely sure which was is the bad one but both seemed low compared to the rest.

So how would I test the Map and TPS circuits to make sure there are no shorts?



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Last edited by lexinator02; 03-30-2010 at 06:55 AM..
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Unread 03-30-2010, 01:10 PM   #22
Que89YJ
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Disconnect the battery. Hook up your ground lead to a good chasis ground point. Set your meter up to measure resistance and read through both pins on the engine connector. If your meter leads are too big to fit in the pins use a paper clip or a strait pin in the pin terminal on the connector. The battery is fused and you didnt say anything about blowing any fuseable links and I am at a loss how you could source that kind of current on the sensor lines. I am with you on this one and real curious on what you find out.
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Unread 03-30-2010, 02:46 PM   #23
lexinator02
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The Fused links on my Jeep are all deleted. They are all cut out and the wires straight wired to the starter relay. Do you think that causes a problem?

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Unread 03-30-2010, 03:55 PM   #24
Que89YJ
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Thats it! That definely caused it to cook! Make the measurements to see if anything is shorted, but replace those fuseable links!
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Unread 03-30-2010, 04:11 PM   #25
lexinator02
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they were deleted like the first week I owned the jeep. Every one looked corroded and cracked. Where do I get replacements?
What size are the fuses?
Can I just use a main fuse on the line running to the starter relay like on an amp?


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Unread 03-30-2010, 04:15 PM   #26
Que89YJ
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Any of the local auto parts store will have them. You still need to figure out why it shorted but it does explain the damage.
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Unread 03-30-2010, 04:30 PM   #27
lexinator02
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so I need to install the 3 or so fuseable links again or can I just install one in the feed line? What rating should they be?
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Unread 03-31-2010, 03:49 PM   #28
lexinator02
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SHE STARTED!!!! I put in a new ecu and she runs but she idles at like 3500.... wtf now?

That is with the throttle blade closed....
I spray carb cleaner all over the engine and the idle didnt change at all.
I also open the butteryfly blade manually and she revved higher.
I plug the little air opening in the inlet of the TB for the sensor I beleive and the idle did not change.
Throttle pedal and cable is not sticking
I drove it around a little and the idle didnt adjust.
Do I have to have the ECU learn or do a reset? I just installed a new one.

I also checked some voltage with key on at the ECU:
the ISA motor forward: 2 volts pin (24)
the ISA motor retract: also 2 volts pin (23)
there was 5 volts at the map/tps pin (16)
TPS pin(31) was at 3 volts


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Last edited by lexinator02; 03-31-2010 at 04:25 PM..
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Unread 03-31-2010, 05:23 PM   #29
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You blew a diode not a resistor. Look at the silver line on one end. That diode keeps current from going the wrong direction in the circuit.
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Unread 03-31-2010, 05:24 PM   #30
msprooch
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I assume that you disconnected the battery when you did the swap???
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