Car has been sitting for maybe 2-3 months. Put the engine back in got everything ready and now i cannot get the tuner to communicate with the pcm. The car WILL turn over fine, but it will not turn my fuel pumps, fan etc. on. It wont take a tune at all, as soon as i try to load it it just gives me a error. I dont know what possibly could have happened in the 2ish months because the battery has been unhooked, and i believe the problem is between the key and the PCM, or the PCM itself. The tune that was on the car has PATS disabled because i had issues in the past but this is different because when turning the key on, no signal is telling the pumps to come on, or anything else for that matter. Ive checked the fuses (no relays) and also went over all my grounds on the car to make sure they were hooked up and tight and everything is good... Im lost and before i go buying another computer maybe someone can help???
No start problem...
- Thread starter Cobra03SC
- Start date
Confirm power to injectors and coils..
than confirm signal on injectors and coils..
a test light is all thats needed and someone to crank engine..or use remote jumper..
im thinking bad ground causing pcm issue..
Ground on motor mount..
ground strap by driver wheel..
ground at battery on radiator support 2 of them
than confirm signal on injectors and coils..
a test light is all thats needed and someone to crank engine..or use remote jumper..
im thinking bad ground causing pcm issue..
Ground on motor mount..
ground strap by driver wheel..
ground at battery on radiator support 2 of them
Last edited:
I had 1 of the 2 grounds on radiator support break..it shut car off and theft went crazy..
the 1 closer to fender..
the 1 closer to fender..
I checked the grounds, 1 at engine under driver fender to heads, 1 on the main starter wire bundle to block, i have the battery in the trunk, with 2 large ground wires both tight and clean to the frame. I have a return style fuel system and normally when the key is turned ON the pumps will also turn on and run. With the key on now, nothing will come on as if the pcm is not sending a signal to turn anything on. The car will still turn over when the key is turned but something is up with the pcm. The tuner also will not program because its throwing a error that it cannot communicate with the pcm. Is there a fuse related to the pcm? I pulled them all but i can check a specific one better if i know what to look for. Also, any relays that could have gone bad? I checked all fuel pump relays and they are all working fine.
Did you also check both power and ground at dlc...?
Have you downloaded the service manual?
It has full wiring diagrams, connecter veiws, pin layout, wire colors and circuit numbers..
It has full wiring diagrams, connecter veiws, pin layout, wire colors and circuit numbers..
Dlc..
pin 16 ..lg/rd wire circuit 1047
12v at all times...
fuse box in car..10amp f2-31
pin 16 is corner of plug on smaller or shorter side of plug as its not square.
pin 4...black..ground..pin 1 is opposite end of plug from pin 16 and is corner of the longer side..
goes to ground by back of radio on passengerside of center..
pin 5...blk/yellow...ground...
goes to that tiny ground on radiator support
using just a test lite you can check all 3 pins...
on ground pins 4 and 5,,if you clip light to 12v..light will light if ground is good
pin 16 ..lg/rd wire circuit 1047
12v at all times...
fuse box in car..10amp f2-31
pin 16 is corner of plug on smaller or shorter side of plug as its not square.
pin 4...black..ground..pin 1 is opposite end of plug from pin 16 and is corner of the longer side..
goes to ground by back of radio on passengerside of center..
pin 5...blk/yellow...ground...
goes to that tiny ground on radiator support
using just a test lite you can check all 3 pins...
on ground pins 4 and 5,,if you clip light to 12v..light will light if ground is good
Last edited:
and all you did was r/r engine....
Wiring shows g104 pin 5 of dlc..also shares this with pcm and ccrm..
Yes, i have pulled this same engine probably 10 times in the last 3 years and never had a issue with anything electrical until now. Ive pretty much memorized every nut and bolt to the point where i just toss them in a bag and put them back on without separating them... Im 99.9% that the wiring is grounded and hooked in, im just not sure if possibly something may have shorted out or blown a fuse somewhere. I had the battery unhooked for most of the time. Was rainy today but im going to follow each and every ground to make sure they are hooked up and cleaned off tomorrow.
Im not doubting your work..looking at what would have been effected or touched during r/r..
there is a connector on both side of car where this ground wire runs to thru harness..both are areas your elbows can hit or tool..
testing the circuit is now only way to tell whats going on..
2 different gronds on dlc...1 powers tool other powers car sensors..
9 out of 10 its just a wire getting pinched...
off topic..im just finishing on nieces car..had short in engine harness causing fuse to blow that contols sensors and trans..
it took spark..car cranked over fine just no start
there is a connector on both side of car where this ground wire runs to thru harness..both are areas your elbows can hit or tool..
testing the circuit is now only way to tell whats going on..
2 different gronds on dlc...1 powers tool other powers car sensors..
9 out of 10 its just a wire getting pinched...
off topic..im just finishing on nieces car..had short in engine harness causing fuse to blow that contols sensors and trans..
it took spark..car cranked over fine just no start
Raining again today ugh. Probably tomorrow ill push it into the garage and try to trace every single wire down that i can find. Is there a way to just remove the computer and have a ford dealer test it? Or a way i can test the computer myself.
If it ran before..I would think its something you did..vs pcm just going..
that ground does run to more than what I listed..and area you were near..
I dont have off hand link..but there is a link that shows whats needed for wiring to get to run..google it..
its something 2v to 4v swap...mix match wiring harness and wire than just need to be moved..
that ground does run to more than what I listed..and area you were near..
I dont have off hand link..but there is a link that shows whats needed for wiring to get to run..google it..
its something 2v to 4v swap...mix match wiring harness and wire than just need to be moved..
Im just not sure if possibly somehow the pcm shorted out while unhooked things, or while putting things back together. I had the battery unhooked while installing it back, but i cannot remember if i had it unhooked while removing the entire time. I know i had it unhooked while messing with the starter, but i cant recall if it was unhooked while disconnecting most other things. Im unhooking all the grounds today and going to grind new bare metal for them to contact to make sure they are 100% good to go.
Ok, checked these. Correct me if im missing something:
Starter wire harness to engine mount:
Driver fender to head:
Battery relocated to trunk, 1 ground in trunk to frame, other to outside passenger wheel to frame:
Driver radiator ground:
Passenger radiator ground:
and just to be sure i pulled the pcm to check the wires and everything looks ok. Ignore blue connector was used for raptor shift light a long time ago:
Starter wire harness to engine mount:
Driver fender to head:
Battery relocated to trunk, 1 ground in trunk to frame, other to outside passenger wheel to frame:
Driver radiator ground:
Passenger radiator ground:
and just to be sure i pulled the pcm to check the wires and everything looks ok. Ignore blue connector was used for raptor shift light a long time ago:
Last edited:
I may be wrong but the ground you have on the head is suppose to be on the driver mount and the starter ground is suppose to be on the bottoms left bolt of the timing cover.
its possible, anyone else know if that is correct or if it makes any difference? I have had them both mounted there for years and the car ran, but the routing may be wrong. I dont think it would cause my issues though. I also pulled fuses and took a very close look at them all and found fuse f1.26 CCRM and fuse f1.1 CCRM both blown. I didnt notice them blown the other day so its possible i may have grounded out something while checking the wires or i missed them. Either way they were replaced with 30 and 50 amp fuses and still did not make any changes.
Ok heres where i am.
Followed a diagram on based on the ccrm. this is what i have found:
Check pin 12 and 24 for 12V if no check 8 and 10(NO)
Check 8 and 10 for 12V (YES)
Check 13 for 12V (YES)
check 15 for ground (YES)
If 8,10,13 and 15 Present, Bad EEC relay inside CCRM
So i have the CCRM out and apart, but im wondering if i should just replace the whole thing or the relay... TBH im not a good electrician and i dont like to solder things because i suck... so new or repair??
Also i cannot find which one is the EEC??? From pictures ive seen none show eec, only fuel,ac,edf/lfc,hedf/hfc, and pcm relays?
Followed a diagram on based on the ccrm. this is what i have found:
Check pin 12 and 24 for 12V if no check 8 and 10(NO)
Check 8 and 10 for 12V (YES)
Check 13 for 12V (YES)
check 15 for ground (YES)
If 8,10,13 and 15 Present, Bad EEC relay inside CCRM
So i have the CCRM out and apart, but im wondering if i should just replace the whole thing or the relay... TBH im not a good electrician and i dont like to solder things because i suck... so new or repair??
Also i cannot find which one is the EEC??? From pictures ive seen none show eec, only fuel,ac,edf/lfc,hedf/hfc, and pcm relays?
Last edited:
So i had a brain malfunction yesterday and assumed the relay was in the ccrm, but i have found it should be near the PCM? Is this correct? Not sure why i thought it was in there because i didnt have the wires plugged into the ccrm anyways lol... but anyways thats the place im going to check tomorrow if it will ever stop raining down here.
Pcm relay is in ccrm..
f126 and f2-34 are power to relay..
pin 8@10 f1-26
Pin 13. F2-34
f126 and f2-34 are power to relay..
pin 8@10 f1-26
Pin 13. F2-34
Users who are viewing this thread
