Bad CCRM? No Fuel...94 Cobra..
 

I've had my Cobra back on the road for two days now. Before the end of my shift this morning I went out to the car and started it to defrost the ice off the windshield. it cranked up fine, no issues. I let it idle for approx. 20 mins. I get in the car and as i'm leaving my work parking lot it hesitates very roughly. I press in the clutch and let it idle down then take off fine. Then, approx a block down the road it does it again and dies. I attempt to start it again with no luck, so i listen for the fuel pump to prime and it doesn't. Luckily, i was uphill from my workplace so i let it roll back to the parking lot and check a few connections and whatnot. Yesterday, i noticed my electric fan was coming on and staying on in ~30 degree weather. I thought maybe Coolant Temp Sensor so i ordered a new one. but then this happens. could this be a sign of the CCRM going bad? i was so tired from working a 13 hour shift that i just jumped in a work vehicle and drove it home instead of messing with it (not to mention it's freezing outside). Any ideas? i'll diagnose more when i go into work tonight....

if the CCRM was bad, you wouldnt get fan functions at all.

Check the grounds for your ECM, especially the two on the radiator support near the battery.

Also, dumb question. but did you remember to put the ground strap back on the drivers side of the block, that runs from the frame to the engine mount, when you swapped the engine?

Any position that includes the defrost will turn on the a/c to clear winshield quickly. a/c on....the cooling fan is on. Check for fuel pressure, spark, then on to EEC1V tests.

thanks adder, i've read some people say that some functions with still work (e.g. fuel pump goes out, but fan still works). bubba, i guess i should've been more clear, the fan will come on and stay on after a cold start in 30 degree whether, even if the climate controls are completely off. i'm back at work and trying to diagnose the problem. ran a jumper to the inertia switch, still nothing.

i did not have a ground strap that went to my motor mount. the only one i have went to the timing cover. maybe whoever pulled the motor last time took it off and didn't put it back on???

FIXED!!!!!! I was close. it was the CCRM fuse in the box. the 20AMP was blown,swapped it with another one to test an the FP came right on. thanks anyways!

I wouldn't call it fixed so quick my friend...what blows a fuse?? = excessive current draw, or short to b+ if it works and doesn't blow immidiately then you have a circuit that is drawing to much current and if that 20 amp fuse is for the fp relay in the ccrm, it may have a pump going on the out.........a quick circuit diagram check would be in order if it were mine, fuses don't just blow, there is a cause, but if your satisfied at stopping short of the cause.....best of wishes and have AAA NUMBER HANDY :)

Right, i replaced it with a 20AMP for the CCRM so it wouldn't fry it untill i have daylight to mess with it. I only live about a mile from my work and i'm off tomorrow, just need some daylight to really check everything. I stuck the 40AMP from the rear window defrost in the fuel pump slot for the time being. I'd rather replace the fuel pump then try to hunt down a CCRM.

Ok, not fixed, it idles and revs fine, but when i try to drive it...fuse blows...wtf....

I suspected as such which is why I posted what I did.........anyway, be careful sticking higher rated fuses in a circuit with a lower rating, could melt wires......as for the prob, get a wiring diagram of that circuit and see what consumers are on that circuit, if the fuel pump is the only consumer on that circuit, it's a good possibility that the windings in the pump have high resistance and following EL-101 basics about electricity, high resistance = current draw up = pop fuses, as long as there are no chaffed wiring on the b+ sise of the circuit the cause is often high resistance in either wiring, connections or the consumer such as the FP. OFTEN TIMES WHAT we uses to verify the prob is a low amp probe around the B+ WIRE ON THE FP CIRCUIT to map the actual current draw, or to get even more technical we perform a current ramp test with a labscope working in conjunction with a low amp probe, and based on the cleanliness of the signal that is output to the labscope it can be easily verified, but in your case I'm sure you don't have such, so grab a diagram and see what load consumers are on that circuit, if it's just the fp than throw a dart and replace it, most likely you'll solve the issue :)

I get what you're sayin..i went and backtracked my steps as to when this issue started..it was when i hooked up heater core back up and i had to move some wiring out of the way to get to it..when i started looking over everything i found a wire with a crimp connector the was laying on metal..dunno if it's related by i moved it and taped it off..im searching for some diagrams now

I'm not narrowing it to the fuel pump, since the pump fuse isn't blowing, the fan fuse isn't blowing, just the CCRM as a whole. here's the diagram i've found so far on sbftech.


http://sbftech.com/index.php?PHPSESS...ach=2652;image

so which fuse on the diagram is blowing ..eec fuse??

yep..

I still say you should add a ground to the block.

feel free to add a ground as adder states but if this prob all started when you moved wires, you'll need to trace the red and yellow wire to what they feed red = pcm relay yellow is supply power to relay but has a bridge for another circuit, so you'll need the other half of this diagram to see where pin 11 and 14 go which are labled at the far left where all wires are in a series.

Reman CCRM Advance $91.47 in June this year includes tax(NC). Called relay control module 1 year warranty. Part # RCM12M sku 20971446 Bubba

Carefully checked all the wiring close to the heater core...electrical taped all exposed wiring (found one that was touching another)...since that it's been fine...hopefully that was the only issue with it..

did a KOEO test and got 117 (ECT sensor is/was low or grounded)

and 542 (Fuel pump open, bad ground or always on - - Power / Fuel Pump Circuits )

got 117 and 998 (hard fault present, ECU operating in failure mode) on the KOER test...didn't show the 542 on the KOER....

Found it!!! one of my oil cooler lines' hose clamp was pressed against my coolant temp sensor...it wore away the insulation of the wire so it grounded itself out on that hose clamp. i moved the clamp and the fan didn't come on as soon as i started the car. Whew, i thought that was gonna be a bitch of some wire tracing. Luckily it was something as simple as that!!!

i'm assuming that was also what was causing the EEC fuse to blow

for future reference do not EVER replace a fuse with a bigger one. I installed car audio security for over 15 yrs and I have seen some HORRIBLE accidents from doing that. One customer had to replace his entire ignition wiring in a 2 yr old honda for a total of $3500 and another customer that set his car on fire....

not likely, since ect is a thermistor and all a short to ground will do is signal to the pcm that resistance is low since a direct ground is provided, AS RESISTANCE goes down temp is precieved to go up, and since you provided a direct path to ground = very little resistance the pcm interpreted this as high engine temp thus signaling the high speed fan operation to cool engine down....now the rubbed through wire would explain why the fans would run right away but not the fuse blowing

I see what your saying..is it a ground only that runs to the ECT sensor? because i believe the insulation was rubbed off both wires..and after i fixed that issue the codes dissappeared for the CPU Failure Mode and Fuel Pump Circuit Open

^^^^i'D HAVE TO HAVE A COMPLETE DIAGRAM OF THE SYSTEM.....to see where everything goes to to see possible scenarios.....the online stuff here is nowhere near as complete as what I use at work for troubleshooting....ahhh didn't know both wires had rubbed through..........in that case thermistors such as an ECT varies the value of its voltage output in accordance with temperature changes, so if the fuses is no longer blowing then your prob could be fixed :)

Yes it was both wires, the fuse is no longer blowing and it's not showing the ECM Failure code anymore. You and adder are a ton of help on here, you guys are smart like college when it comes to 5.0's

no problem^^^^ FYI , I do this for a living, I learn a new thing every day too!!! :)