1991 ECU ECM pinout
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1991 ECU ECM pinout
So, the 1991 and 1992 FSM's are different than the others when it comes to trouble shooting the ECU.
I went to our local king county library and found the following pics to help me out.
The first picture is of the pinout. The following pictures are some flow charts for evaluating the ECU. I'm struggling with these right now because I've got fuel issues. My question is below the first picture.
For reference, the "W" wire is a dark purple, while the E1 is brown.
Step 1 in the following picture, it says I should have no voltage when I short the B+ and B+1 and measure it with the E1. But I do in fact get a volt reading (12 v).
And the 2nd step of that same picture, it says I should get a reading, but I don't.
Does that make any sense to you all? What does this mean for my ECU?
trouble shoot 1
trouble shoot 2
trouble shoot 3
[IMG]https://i.imgur.com/RV9nn0e.png[/I
I went to our local king county library and found the following pics to help me out.
The first picture is of the pinout. The following pictures are some flow charts for evaluating the ECU. I'm struggling with these right now because I've got fuel issues. My question is below the first picture.
For reference, the "W" wire is a dark purple, while the E1 is brown.
Step 1 in the following picture, it says I should have no voltage when I short the B+ and B+1 and measure it with the E1. But I do in fact get a volt reading (12 v).
And the 2nd step of that same picture, it says I should get a reading, but I don't.
Does that make any sense to you all? What does this mean for my ECU?
trouble shoot 1
trouble shoot 2
trouble shoot 3
[IMG]https://i.imgur.com/RV9nn0e.png[/I
#2
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You're reading the consequence backwards. You are supposed to have 12v from B+ to E1 with key on. Only if you don't do you need to proceed with the troubleshooting. [The next step checks the E1 connection to ground; if you don't have 12v B+ to E1, you don't know if its B+ or E1 that's broken, so it bypasses E1 by connecting directly to the frame.]
So, if you have 12v B+ to E1, you HAVE to have 12v B+ to body ground (frame). Something went wrong in your test.
(By the way, please don't say "no reading" when using a multimeter. 0.0v is a reading, just like 12.6v is a reading. Yeah, I can guess you mean 0v when you say "no" reading for voltage, but what do I do when you're measuring resistance?)
So, if you have 12v B+ to E1, you HAVE to have 12v B+ to body ground (frame). Something went wrong in your test.
(By the way, please don't say "no reading" when using a multimeter. 0.0v is a reading, just like 12.6v is a reading. Yeah, I can guess you mean 0v when you say "no" reading for voltage, but what do I do when you're measuring resistance?)
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