03 MACH 1 CCRM BUZZING/ CLICKING

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I think the grounds were 13, 15,16, maybe i will check again tomorrow what they read because if these had weak grounds, where are these grounds located? all over the car? I know one was good, and the other 2 grounds were low, i think

ill get back to you tomorrow with the results!
 
Pin . . wire color . . . . . . function
==================================
1 - red / orange --- low speed fan
2 - red / orange --- low speed fan
3 - yellow / black - fused battery +
4 - yellow / black - fused battery +
5 - green / yellow - fuel pump
6 - orange / blue -- high speed fan
7 - orange / blue -- high speed fan
8 - black / orange--- fused battery +
9 - not used
10 - black / orange ---fused battery +
11 - blue / orange ---- fused battery +
12 - red ------------ 12V with key On or Start
13 - white / blue -- 12V with key On or Start
14 - blue ------ low fan relay
15 - black / white --- Ground
16 - black --- Ground
17 - green / violet --- high fan relay
18** black ----- Ground
19 - not used
20 - not used
21 - green/orange ----- fused battery +
22 - pink / yellow ----- A/C clutch relay
23 - black yellow ------ A/C clutch
24 - red ---------------- PCM power

** for Cobra, pin 18 is white; fuel pump control

With the negative meter probe connected to chassis or battery negative terminal, all Ground pins should measure zero volts.
 
alright I broke down and took it to ford for a diagnostic for 99$ (I had school and running out of time, and my step dad has a tow truck so he towed it there) but i was confused as hell and they said they are 95% sure they could find the issue, but there confused. The tech said if i find out whats wrong to let him know.

THE GOOD THING IS IT RUNS if I rig it up


I have to have the 2 BLK/ORANGE (8,10) from the CCRM and the RED (24) all touching at the same time.... BUT YOU HAVE TO LEAVE THE BLACK GROUND OUT AND TOUCHING NOTHING!

he said if the black ground is in the CCRM that it just starts buzzing. The tech said he would replace the CCRM, but I put this CCRM in my friends car and it started right up, Also I bought a new CCRM and it started right up in my freinds car.... It just buzzes in my car
 
What the tech did was jump (bypass) the PCM relay contacts within the CCRM. This test proved your PCM, PATS, fuel pump, etc. were all good. It also proves the PCM relay was not operating properly, but we don't yet know for sure if the cause is within or external to the CCRM. We also still do not know which of the 5 relays inside the CCRM was buzzing. It is possible there are 2 different problems and the CCRM buzzing is just a coincidence (but I doubt it).

What we know so far points to either a bad CCRM ground or a failed connection within the CCRM, preventing the PCM from being powered. Your test with a friend's car supports the bad ground theory, because your CCRM evidently worked in his car. If the tech jumps each of the CCRM ground pins (15, 16, & 18) to a known good ground and the problem clears, it will confirm a bad ground. If no change, the problem could be in the CCRM connector or the CCRM itself.

If the tech has a replacement CCRM in stock, it's probably easier to first try a replacement before bypassing the ground connections.
 
well I have the car back in my driveway because i have the weekend to work on it, was trying to find the problem asap so thats why i took it to ford and i work and school at night

so should i test the grounds to the battery and make sure i get full power, and if not are you saying just splice the pins 15,16,18, to a ground.

im confused because he only had 8.10.24 connecting, so bypassed the ground?
 
To verify the CCRM ground, you just have to temporarily jump/splice either Pin 15 or Pin 16 to a good ground and see if the buzzing stops. Pins 15 and 16 are connected together inside the CCRM, so no need to jump both. Pin 18 is a dedicated ground for the fuel pump relay and must be OK or the engine would not have run for the Tech.

If the buzzing does not stop, a bad CCRM ground is not the cause.

The next thing to try (in fact, I would do this test first) is to temporarily remove Fuse 2.34 (20 Amps) and see if the buzzing stops with the key On. If it does, leave the fuse out and temporarily jump Pin 13 to either Pin 8 or Pin 10. If the buzzing stops and the car starts it indicates a problem with either the ignition switch or CCRM-to-ignition connection (wire or connector).

Jumping Pins 8, 10, and 24 takes the CCRM out of the PCM circuit (bypasses it), connecting battery positive directly to the PCM. The CCRM Pin 15 and 16 grounds are not needed for the PCM to receive power when this jumper is in place.

The $99 diagnostic charge appears to have been well-spent, since the Tech saved you the $400 it would have cost for a used PCM and new keys.

Is your voltmeter a digital type (an LCD display with 3-4 numbers)? If yes, it would explain why you cannot measure a low PCM voltage while the CCRM is buzzing.
 
well i bought a PCM and got it for 225, so if u know anyone that needs one send them my way! ill sell it on ebay soon.

but pin 18, the solid black ground, is out of the ccrm connectiona nd the car still starts?

and I will do these test tomorrow, had a busy weekend so ended up not working on it.

but im using my step dads voltmeter, it displays like 4 or 5 numbers, but has different knobs on there where i can switch how much it reads, Im not sure I know how to get it to display the 12volts. and etc for a normal reading.(I dont know much about the eletrical field)
 
do you know if the transmission wiring is somehow connected to the ccrm or could cause a short, just asking because my o2 sensor was dragging and disconnected, might have ripped the transmission wiring up towards the bellhousing where i could barly see.
 
Automatic transmissions have several internal solenoids and a temperature sensor that are all wired directly to the PCM, and the PCM is powered through the CCRM.

Digital voltmeters are sometimes "tricked" into false readings when measuring pulsed-DC. That might explain why you measured full battery voltage out of the CCRM while buzzing.

With pin 18 disconnected from ground (and assuming the Ford electrical drawings are correct), the fuel pump should not operate. But the engine could still start and run for awhile on the pressurized residual fuel stored in the filter, fuel rails, and fuel lines.
 
Thats what I am confused about, the tech said he drove it around and had it running for 15mins. and I have had the car running for 10 mins, I think the fuel rails and lines would have been dry by now?

and the car is a manual
 
Manual transmission models just have an output shaft speed sensor that connects to the PCM.

Read the "fuel filter" message thread on this page. The poster disabled his fuel pump and the engine continued to run for more than 20 minutes.

I doubt if the tech "drove around" with temporary jumper clips hanging off the CCRM, particularly since one has to remove a wheel to access it. The problem to diagnose was "no-start", so there was no need to actually drive the vehicle. Sometimes words are misunderstood and/or comments embellished.

The heaters in the oxygen sensors connect to pin 24 of the CCRM through fuse 2.8. So it is possible for a short between O2 heater and ground to cause upstream damage to electrical wiring or components. The fuse is supposed to prevent such damage, but sometimes folks replace a blown or suspect fuse with one of higher amperage, intending to buy the right size later, and then forget.

What is known (based on tech and owner reports):
Bypassing the PCM relay in the CCRM allows the engine to start and run.
The CCRM is not defective; it worked fine in another vehicle.
The CCRM buzzes or clicks when the ignition is turned on.

What is unknow:
Which relay within the CCRM is buzzing?
Why is the CCRM buzzing? Is there a fault in the CCRM power or ground circuits?
Hopefully the recommended experiments/tests will provide clues to the answers.