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Discussion Starter · #1 ·
Hey I could really use some help from the mustang gurus I recently replaced my motor and am now getting 3 different codes. A U1262 -SCP (J1850) Communication Bus Fault a P0357-Ignition Coil Primary circuit malfunction cylinder 7 and a p0307 missfire cylinder 7. Now the bus fault has me the most concerned and im really hoping its not a fried pcm that's causing it. I did notice today that the grounding strap from the block to the motor mount is not connected must have missed that on re assembly. The car starts right up and sounds fine to my amatuer ears don't hear a missfire or a dead cylinder. Could the grounding strap not being attached cause these codes? Also my headlights are not working. Everything else does as far as lights. The high beam indicator doesn't light when you try to flash it or put it on high beams I was also wondering if that strap could cause that problem as well. I'd really appreciate any help its our only car and we both work so it's a must fix asap situation but limited funds.
 

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I would say that grounding strap would cause some problems now what problems I do not know. Are you still getting the codes now? So now that the ground is attatched the car runs fine? Check all grounds for headlights, and fuses. I had a problem with my headlights I have projector headlights same deal with mine but the bright light indicator would light up when on my power wire running to the battery had a fuse and the fuse was bad looking not getting a good contact easy fix but took some tracking down to find to be something so simple.

wmburns is very good in these parts if you can clear up a little like the questions I asked he will probably point you in the right direction.
 

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I'm all over this one!

Check the ignition fuse F1.26 BJB.

Check fuses F2.2, F2.8, F2.34 in the CJB.

F1=BJB=Battery Junction Box-located in the engine bay
F2=CJB=Central Junction Box-located in the driver's kick panel.

Not a bad idea to review all fuses as there are tons of "always on" circuits. They are easy to blow if working on the car without first disconnecting the battery negative.

The SCP error is most likely a missed ground connector. There are two round connectors with black wires with white stripes (BK/WH). One is on the right hand engine bay near the radiator core support. It's easily missed because it's under the intake tube.

The other is on the left hand side under the battery junction box. Again easily missed because it's under the BJB.

As "fordman777" mentioned, the motor mount grounding strap is important. Ensure it's making a good connection.

If unable to find it, double check your work for missed connectors. If still unable to find it, additional tests will be required to narrow down the problem.

The P0357 DTC is because the PCM is not seeing 12 volts on the COP return wire at #7. This could be from a break in the wire. However, I'm betting after an engine swap this is something simple like a loose connector on the COP itself. Check to be sure the connector is pushed in all the way and making good connection.

If unable to resolve this, confirm there is +12 volts on the COP Red wire with the key on. Check several COP's as there should be +12 volts on all of them when the key is on.

Post back the results. Good luck on the swap.

Here's a quick link to the BJB CJB panel layout.
http://www.allfordmustangs.com/foru...r-swap-wont-fire-please-help.html#post2669271
 

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Discussion Starter · #4 ·
Checked all fuses every one showed good. Ground plugs were connected. Going to try swapping cops for known good one on cylinder 7. Also going to try to get better connection for the grounding strap. Still no headlights going to see if maybe some how blew both bulbs due to a surge but since high beam indicator isn't working either I have my doubts. Thanks for the help so far this is getting really frustrating lol
 

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A couple of tests please.

Check the main battery cable connection to the BJB. Make sure it's tight. Double check all battery cables to be sure they are clean, tight, and corrosion free. Check the grounds around the battery and radiator core support.

Confirm if the low beams work or just the high beams not working.

Pull fuse F1.2 in the BJB and verify there is +12 volts to the input side of the fuse socket.

Pull fuse F2.38 in the CJB and verify there is +12 volts in the input side of the fuse socket with the high beams on.

Was any work done behind the dash? The cluster is grounded at G204. G204 is a very important ground used by the cluster, radio, GEM, PATS, SCP communication bus. Seems like a very important symptom that two of the reported symptoms share a common ground.

If G204 is bad, this would keep the high beam indicator from working. This would also affect the cluster to PCM communications as well as the ODB2 data port.

G204 is located behind the center console very near the radio. There are several black wires that come together at that point.

Did you have any other difficulities during the swap? Pull on any wiring harness? Have difficulity re-attaching any connectors? Bent pins? Note any water damage or evidence of overheating on any connector?

Are all of the symptoms in the opening post still present?
 

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Discussion Starter · #6 ·
A couple of tests please.

Check the main battery cable connection to the BJB. Make sure it's tight. Double check all battery cables to be sure they are clean, tight, and corrosion free. Check the grounds around the battery and radiator core support.

Confirm if the low beams work or just the high beams not working.

Pull fuse F1.2 in the BJB and verify there is +12 volts to the input side of the fuse socket.

Pull fuse F2.38 in the CJB and verify there is +12 volts in the input side of the fuse socket with the high beams on.

Was any work done behind the dash? The cluster is grounded at G204. G204 is a very important ground used by the cluster, radio, GEM, PATS, SCP communication bus. Seems like a very important symptom that two of the reported symptoms share a common ground.

If G204 is bad, this would keep the high beam indicator from working. This would also affect the cluster to PCM communications as well as the ODB2 data port.




G204 is located behind the center console very near the radio. There are several black wires that come together at that point.

Did you have any other difficulities during the swap? Pull on any wiring harness? Have difficulity re-attaching any connectors? Bent pins? Note any water damage or evidence of overheating on any connector?

Are all of the symptoms in the opening post still present?
No power to the 50 and 30 for the cooling fan (fan was inop also hard wired it and it still works just no power) and headlights all others have voltage checked where cable connects from battery and the post had been torques over to hard and has pulled the lines going to those circuits. Basically to fix right need a new bib going to try to open up the bottom and see about reconnecting the wires. All other issues fixed cylinder 7 the connector going to the COP was loose tightened that up reset comp no new codes are showing now. How much are hubs and how big a pain are they replacing seems like there is a lot of wires going into this thing. Thanks for the assistance!
 

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If I understand the post, the main post to the battery junction box was over tightened and pulled several wires apart. This has made several circuits in the BJB "dead".

Honestly this looked like a power problem to me. However, I wouldn't have thought about over tightening the BJB bolt.

As for how much is a replacement BJB, try car-part.com to search salvage yards in your area.

It seems to me that someone with enough skill to replace a motor can repair a few wires. But then again I don't know the extent of the damage. Can you post pictures?

Sounds like I nailed the issue with #7.
 

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Discussion Starter · #8 ·
If I understand the post, the main post to the battery junction box was over tightened and pulled several wires apart. This has made several circuits in the BJB "dead".

Honestly this looked like a power problem to me. However, I wouldn't have thought about over tightening the BJB bolt.

As for how much is a replacement BJB, try car-part.com to search salvage yards in your area.

It seems to me that someone with enough skill to replace a motor can repair a few wires. But then again I don't know the extent of the damage. Can you post pictures?

Sounds like I nailed the issue with #7.
Definitely hit the nail on the head with cyl 7. As for the bjb I was able to cut away the bottom of it and straighten out the power supply bar and push it back up and now have headlights and fan works again. Thanks for the assist now to fix the pinion seal and replace tranny mount and she should be a healthy horse again.... might go ahead and sneak some 4.11 gears in her butt without the wife knowing when I have the rear end apart lol thanks again!
 
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