Is my CCCU toast?

EamonnDH

EamonnDH

Member
I'm halfway through digging out the lock mechanism on the rear right door to check if that is corroded or similar, but hoping someone can make an educated guess on what's going on here. See pics for codes.

Symptoms include the alarm going off seemingly randomly. Locking/unlocking via key fob doesn't shut it up, but seemingly just mashing random buttons on the dash eventually calms it down. But, if you open a door it goes off again.
979c67a30e8175fd4e39d0075042c101.jpg
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EamonnDH said:
I'm halfway through digging out the lock mechanism on the rear right door to check if that is corroded or similar, but hoping someone can make an educated guess on what's going on here. See pics for codes.

Symptoms include the alarm going off seemingly randomly. Locking/unlocking via key fob doesn't shut it up, but seemingly just mashing random buttons on the dash eventually calms it down. But, if you open a door it goes off again.
979c67a30e8175fd4e39d0075042c101.jpg
22f9806a2f4f0e2612c6b03dfa32d94d.jpg
Click to expand...

If you scan your CCM what do you get?


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What is the last letter n your cccu ?
If it’s Q then you have the very unreliable version and the symptoms you are describing are aligned to a failing cccu
A scan may or may not yield anything

Paul


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depronman said:
What is the last letter n your cccu ?
If it’s Q then you have the very unreliable version and the symptoms you are describing are aligned to a failing cccu
A scan may or may not yield anything

Paul


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Click to expand...
It's an F. I'll try to scan it later today.
 
You have a lot of stored faults some will be historical
I start by clearing them all out and then scan again after 15 mins and operating everything concerned and see what is still there

Paul


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depronman said:
You have a lot of stored faults some will be historical
I start by clearing them all out and then scan again after 15 mins and operating everything concerned and see what is still there

Paul


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Click to expand...
I managed to clear some of the faults, but I couldn't really get it to communicate with the CCCU. It was worse than ever before, I could hear relays in the CCCU going absolutely bananas.

At one point the boot and the fuel filler cap opened themselves, and generally everything was a bit mad.

Dead CCCU?
 
I don't know what software/hardware was used to retrieve the fault codes, but the scan results are a bit vague. That said, there's plenty of evidence that the CCCU has thrown its toys out of the pram: the F variant of CCCU is every bit as unreliable as the Q variant mentioned previously, the relays within the CCCU going nuts is a common symptom, the instrument cluster appears to have lost communications with daughter electronics, etc, etc.
The CCCU is frequently wrongly convicted of crimes it didn't commit, so I'm often hesitant to diagnose a faulty CCCU before getting my own hands on the car, but I'm fairly confident that a replacement CCCU will cure your car's problems.

Cheers,

Tom
 
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timmus said:
I don't know what software/hardware was used to retrieve the fault codes, but the scan results are a bit vagu. That said, there's plenty of evidence that the CCCU has thrown its toys out of the pram: the F variant of CCCU is every bit as unreliable as the Q variant mentioned previously, the relays within the CCCU going nuts is a common symptom, the instrument cluster appears to have lost communications with daughter electronics, etc, etc.
The CCCU is frequently wrongly convicted of crimes it didn't commit, so I'm often hesitant to diagnose a faulty CCCU before getting my own hands on the car, but I'm fairly confident that a replacement CCCU will cure your car's problems.

Cheers,

Tom
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Thanks for the info timmus I've got a new one arriving Wednesday. From the same year, engine and general spec. I should just need to program the keys and be done with it, right?
 
EamonnDH said:
Thanks for the info timmus I've got a new one arriving Wednesday. From the same year, engine and general spec. I should just need to program the keys and be done with it, right?
Click to expand...
Assuming the 'new' CCCU is coming from a UK-spec car, then a majority of its software settings will be correct. However, the CCCU needs to be told how many electric windows are present, and whether or not the car has climate control. You'll then also need to programme the remote key fobs, as you rightly say.
Be aware that the early CCCUs are all fundamentally flawed and are ticking time bombs. You may be lucky and find that the replacement that you've bought lasts for a good few years, but it will eventually go wrong in one of many ways.

Cheers,

Tom
 
timmus said:
Assuming the 'new' CCCU is coming from a UK-spec car, then a majority of its software settings will be correct. However, the CCCU needs to be told how many electric windows are present, and whether or not the car has climate control. You'll then also need to programme the remote key fobs, as you rightly say.
Be aware that the early CCCUs are all fundamentally flawed and are ticking time bombs. You may be lucky and find that the replacement that you've bought lasts for a good few years, but it will eventually go wrong in one of many ways.

Cheers,

Tom
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In which case, what's the longer term solution? Surely we're all going to run out of functioning CCCUs eventually?

Can they be refurbed? I'd guess it needs more than a couple new relays in it. I did have a look at the board on mine and I couldn't find any signs of corrosion or damage.
 
Failing Motorola chip on early cccu if memory serves me
Fixed on latter cccu models eg AF units
Paul


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EamonnDH said:
In which case, what's the longer term solution? Surely we're all going to run out of functioning CCCUs eventually?
Click to expand...
The second-generation CCCUs, such as the AF variant, are near bulletproof. In all my years of working with A2 electronics, featuring countless CCCU replacements, I've encountered only two failed 2nd-gen CCCUs.

EamonnDH said:
Can they be refurbed? I'd guess it needs more than a couple new relays in it. I did have a look at the board on mine and I couldn't find any signs of corrosion or damage.
Click to expand...
Yes, they can be refurbished, but that path is more costly than replacing your 1st-gen CCCU with a 2nd-gen CCCU. Opening a failed 1st-gen CCCU won't reveal any clues as to what's gone wrong. The problem is created by dodgy software in a Motorola chip rather than a hardware problem.

Cheers,

Tom
 
timmus said:
The second-generation CCCUs, such as the AF variant, are near bulletproof. In all my years of working with A2 electronics, featuring countless CCCU replacements, I've encountered only two failed 2nd-gen CCCUs.


Yes, they can be refurbished, but that path is more costly than replacing your 1st-gen CCCU with a 2nd-gen CCCU. Opening a failed 1st-gen CCCU won't reveal any clues as to what's gone wrong. The problem is created by dodgy software in a Motorola chip rather than a hardware problem.

Cheers,

Tom
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Shame, good to hear the AFs live on though. If this replacement I've ordered solves the problem I'll keep an eye out for an AF to keep on the shelf should the inevitable happen.

Thanks for the help guys
 
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