89 electrical

Am I correct? There's four connectors on the ECM--A, B, C, and D.

When they're ALL unplugged, and you connect power to C16 and ground to D1, the fuse doesn't blow.

What happens if you connect the entire "C" connector, and the ground to D1? What happens if you connect power to C16, and the entire "D" connector? The entire "B" connector?

Wild Guess with no evidence: It'll be fine until you plug in the "A" connector. (But I've been wrong before.)

Schurkey said:

Am I correct? There's four connectors on the ECM--A, B, C, and D.

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There's 2 physical connectors with 2 rows in each, one has A & B, and the other has C & D. B1 and C16 have 12V from battery. A11 & D2 are sensor grounds while A12 & D1 are system grounds. I'm thinking some other wire is going to direct ground when it s/b going to a device. Maybe take an Ohm Meter to each wire, in each connector and verify one or more are grounded when they shouldn't be.

Here's a link that may help too. Page 8 shows the connectors. HTH

OK. Connect the C & D connector with the A (and B) connector unhooked. See what happens.

If the fuse doesn't pop, de-pin A1, then connect the A/B connector.

In short, I'm suspicious of A1.

Schurkey said:

Connect the C & D connector with the A (and B) connector unhooked. See what happens.

Click to expand...

I see where you're going with this. At least you're cutting possibilities in half by doing that, which is a good troubleshooting method. If it blows the fuse with C&D connected and A&B disconnected, we'll narrow it down to C&D. If not, go to A&B. Yes, the fuel pump lead (A1) may be shorted out somewhere.

BTW, here's how to de-pin your connector...
www.dynamicefi.com/RePinHowTo.php

Mathies said:

No fuel pump prime. Changed fuel filter an fuel pump (it wasnt bad but changed bcs it would probably go bad in the nezr future). Stil no prime. Replaced fuel pump relay still no prime. If i jump relays pump works fine.

Click to expand...

Schurkey said:

In short, I'm suspicious of A1.

Click to expand...

which is the fuel pump relay control circuit.

PlayingWithTBI said:

I see where you're going with this. At least you're cutting possibilities in half by doing that, which is a good troubleshooting method. If it blows the fuse with C&D connected and A&B disconnected, we'll narrow it down to C&D. If not, go to A&B. Yes, the fuel pump lead (A1) may be shorted out somewhere.

Click to expand...

We know that there's problems with the pump relay circuit. Seems reasonable that the relay circuit and the fuse popping/ecm failure are related.

thx for the answer and method to de-pin m connector.

i tried connecting only A and B and unhooking C D and the other way around the fuse still pops.

i also measured ohm between all the pins on the connector and ground only B8 has continuety to ground and ofcourse D1 and A11.

B8 goes to the AC clutch and AC accumulator like you see on the wiring scematics
also connector c323 is disconnected.
When disconnecting the AC clutch b8 isnt connected to ground and the fuse still pops.

ill try to de-pin the ecm connectors pin by pin and connect them to ecm to eliinate as many wires.

could it be that the wires are grounded when going through the firewall? and any way to open that plastic thing i think its called grommet 100 like on the wiring shematics

Hello i think i found the issue tot the problem although i hope so. After further inspection of the ecm i saw what you guys can see in the picture what looks a slightly burnt solder on the pins on the delco 60904. I found a video of a guy repalcing it and he states the ecm was unable to fire up the fuel pump and open the injectors the same issue im having. Now the question is if can find a guy that would replace that for me does the number 8837 matter if i buy a new delco 60904? Like the one with the blue background?

I hope you can see it on the picture

C16 is protected by a 10 amp fuse in the fuse panel. it does not power the fuel pump. if it keeps blowing then theres something wrong with the ecu. just go get a different ecu these things are not hard to obtain. swap your memcal over. done.