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BROKE DOWN - Engine Control Unit DTC's / U1007

OP
Rhinopolis

Rhinopolis

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Thread Starter #41
Have you unmarried the AP to go back to stock completely?


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I have not, and would you mind briefly explaining why this potentially could correct the issue? Thank you.

Open the engine bay fuse box. See if all is dry and clean in there and all fuses are seated properly. I have seen some guies in my neck of the woods get snow and salt in the box which is not good for connections.
Good suggestion and I did that yesterday. All looked good.

Damn, this sucks. Big time


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It's definitely frustrating, and yes it does sucks big time
 


OP
Rhinopolis

Rhinopolis

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Thread Starter #42
Have you unmarried the AP to go back to stock completely?


Sent from my iPhone using Tapatalk
I have not, and would you mind briefly explaining why this potentially could correct the issue? Thank you.

Open the engine bay fuse box. See if all is dry and clean in there and all fuses are seated properly. I have seen some guies in my neck of the woods get snow and salt in the box which is not good for connections.
Good suggestion and I did that yesterday. All looked good.

Damn, this sucks. Big time


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It's definitely frustrating, and yes it does suck big time
 


OP
Rhinopolis

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Thread Starter #45
I've checked all connections, unmarried and remarried the AP, etc. I drove the car 50 miles yesterday, and it's running really well. I will be mixing to E30 after this weekend and then switching from the 93 map to the E30 one, and if that causes the issue again then I will suspect that it's somehow related to that. I don't have any reason to suspect this since I have been running on this same E30 map since June, and since I completed the tuning process with the X37.

Weird thing, and I datalogged on the 93 map (even though the tank was 4.5 gallons of straight 93 and the rest is E30), and my 3rd gear pull on VD netted 282 peak whp.....lol. I peaked out at 23 psi and this tune file and datalog show nothing to be concerned about and was not "optimized" by my own choice and since I only wanted to tune on E30. I just thought this was interesting and I hadn't ever driven/datalogged the car on the 93 tune file before. It feels peppy for sure, and perhaps it's the higher than usual ethanol % that's giving the unexpected gain?
 


Hijinx

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#46
Be wary when running extra ethanol on 93 maps.


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Hijinx

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#48
Wat?

Went to edit my post real quick, and thought I quoted myself. So confused right now. Hopefully someone quoted it before my screw up.

Cliffnotes: fuel delivery requirements are slightly different. May run lean with too much E85. Talk to your tuner. I'm just some guy on the internet.
 


OP
Rhinopolis

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Thread Starter #49
[MENTION=759]Hijinx[/MENTION]

I appreciate the heads up and you're a good resource. I constantly monitor the vitals and as I drive, and I'm not running lean.
 


OP
Rhinopolis

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Thread Starter #51
I believe that I might have a reason for what happened, and someone more knowledgeable please chime in. Skip to number 5 if you don't care about the recap. Recap.......

1. I snapped the three mounting bolts that secure the RMM bracket and RMM to the engine. Who knows why this happened, and it occurred on an aggssive 1-2 upshift toward the end of September. The bracket was lost, and I had to drill the snapped mounting bolts out and clean the threads. I ordered a CP-E RMM because it comes with a new bracket, and then I ordered replacement studs.

2. I have upgraded TTR engine and transmission mounts, and this might have kept me from immediately feeling that I was missing the RMM support. I heard the "POP" when the bolts broke, and initially chalked it up (after inspecting the car and not being able to see under it) to perhaps hitting some road debris that kicked up under the car.

3. I drove the car, and even drove it aggressively. Finally I started feeling a little slop in the gear changes, and then I could hear the RMM "swinging" on the chasis mounting point and hitting up under the car a little. I drove it home and parked it until I repaired the issue.

4. It was slightly over one month (I had been traveling for work) before the issue was repaired, and on the 1st test run all was running great until the car went a little "crazy".

5. The instructions on the RMM say to disconnect the negative battery terminal, which I did not do. Did I perhaps "ground" the car and the reaction to me grounding it was delayed? There have been no more issues and all electrical connections appear on securely and the car seems to be "over" what the issues were.
 


haste

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#52
Do you disconnect the battery from the car when using the trickle charger? What type of trickle charger do you have?
 


OP
Rhinopolis

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Thread Starter #53
Do you disconnect the battery from the car when using the trickle charger? What type of trickle charger do you have?
No, I didn't disconnect anything. I don't know if it's a "trickle charger" and it maintains the battery or charges it. I purchased it at Walmart and have been using it without issue for years. It plugs in to the wall, and then has a positive and negative connection that clamps on to the corresponding battery post. There is a light in the face that tells if it's "charging" or "maintaining".
 


CanadianGuy

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#54
Not the rmm. Never disconnected it and would never. It's not electrical. Would be like saying disconnect the battery to replace the spare tire. Likely the install sheet was a template and it reused that section.

I have seen trickle chargers not play nice with electrical systems. Maybe worth looking into it.
 


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#56
Quick test/fix. Remove the battery connection. This will reset the ECU. Wait 1-3 minutes and restart. It should idle rich as it learns again. Also I have found out that the wrench light comes on when the cruise control signals are affected. A brake pedal switch or even and accelerator pedal switch would fire the wrench light. Reading what happened to you. You may have a pedal issue. Did you disconnect the accelerator pedal recently? Check the connection to be sure.
Hello, I'm also having trouble with a wrench light.. ever since i visited the dealer and got a 30k service(as well as new brakes) the wrench light comes on. It does not come on all the time, but very often and whenver it does come on, i can no longer activate cruise control. Whenever the light is off however, I am able to use cruise control. Would you recommend plugging/unplugging said "brake/accelerator pedal switch"?
 


CanadianGuy

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#57
Hello, I'm also having trouble with a wrench light.. ever since i visited the dealer and got a 30k service(as well as new brakes) the wrench light comes on. It does not come on all the time, but very often and whenver it does come on, i can no longer activate cruise control. Whenever the light is off however, I am able to use cruise control. Would you recommend plugging/unplugging said "brake/accelerator pedal switch"?
Likely it is the switches but also check your brake fluid level. The dealer can also scan for the extended proprietary codes and see what's up.
 


M-Sport fan

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#59
Not the rmm. Never disconnected it and would never. It's not electrical. Would be like saying disconnect the battery to replace the spare tire. Likely the install sheet was a template and it reused that section.

I have seen trickle chargers not play nice with electrical systems. Maybe worth looking into it.
Same here, as I also did not disconnect the negative terminal when I installed my cp-e RMM, and have had NO problems whatsoever in the almost 5 months since it was done.

One other suggestion on the use of chargers;
My Diehard/Odyssey AGM and the Odyssey/Schumacher dedicated/specific charger for it (used on my 4th gen LS1 f body) stated that the negative clamp from the charger should ALWAYS be connected to a (UNI)BODY/CHASSIS ground, and NOT directly onto the battery's negative terminal.
I don't know just how much actual bearing/negative effect not doing this could cause, but thought I'd mention it so others could chime in and concur or refute it's validity. ;)
 


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#60
FWIW, I had a U1007 code set as well. It was caused by a blown fuse, located inline with the battery monitoring sensor.
There's a small single yellow / violet wire coming from the BMS, runs alongside the ECU enclosure, to a small connector which is attached under the red cover of the positive terminal. Inside of the connector, you will find a 3A light purple fuse.

This circuit is for battery monitoring. U1007 was set in my car, due to the battery terminals corroding; and then the corrosion finding its way into the connector and eventually blowing the fuse.
Your results may vary, but if you've had it on a battery tender, it may be worth it to check this fuse. See below.
bad little fuse!.PNG

Since my connector, battery terminal and battery were effed, I went ahead and replaced the battery.
See pics of corroded fuse holder.
The OEM terminals were so corroded, that I wasn't able to remove the positive terminal. So, I had to improvise with parts from Vatozone.
I found a terminal assembly off the shelf which fit, and then replaced the corroded fuse holder and section of wire with OTS parts.
Once my repair was complete, code was gone.

PM me if you aren't able to find it, I can help you :)
 


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