Permanent Solution to CEM issues

[Cornish Expat]

Is there a permanent solution to the electrical issues that seem to plague early P1 cars?
After being stranded due to ‘Brake Failure stop immediately”, Cleaning the CEM, being fine for 6 months then getting stranded again, wiggling the connections to the CEM, being fine for a week, getting the “anti-skid failure” message that precedes complete stranding, wiggling the CEM and being fine again I’m starting to get fed up driving a car that could strand me at the side of the road at any time.
Is there a permanent fix for a dodgy CEM or am I just going to have to dismantle everything and clean it every couple of months? If that’s the case then the car really isn’t fit for purpose as its going to have to be used for commuting soon.

[SwissXC90]

Yes there is a permanent fix.

If your CEM is unreliable, replace it with a brand new one.
That will solve many reliability issues.

Of course, such a fix comes at a price - but it is the fastest and simplest way to resolve the issue and ensure reliability.

[Cornish Expat]

Thanks, I didn’t realise it was as simple as that, most online advice stops after “clean the CEM with a nylon brush”. Has anybody got any experience of doing this? Are reconditioned CEMs worth looking at (the car’s only worth £2k) or should I go new?

[SwissXC90]

Originally Posted by Cornish Expat

Thanks, I didn’t realise it was as simple as that, most online advice stops after “clean the CEM with a nylon brush”. Has anybody got any experience of doing this? Are reconditioned CEMs worth looking at (the car’s only worth £2k) or should I go new?

Brand new electronics are more reliable than 2nd hand or reconditioned.
That's because brand new has less operational hours on it than old.

You can clean and try and recondition CEMs. You may be successful. Or may not.

New parts come with guarantees and reliability but always come at a cost.

And cost vs effort vs gains is a very personal decision that you make based on your value of the car, your personal financial situation, and the effort you want to invest.

[FunkyMelon]

Originally Posted by SwissXC90

Yes there is a permanent fix.

If your CEM is unreliable, replace it with a brand new one.
That will solve many reliability issues.

Of course, such a fix comes at a price - but it is the fastest and simplest way to resolve the issue and ensure reliability.

Rubbish. OP, please don't follow this advise.

I spoke to a family member at Volvo recently when I had this problem and 99% of the time it's never the CEM that's at fault, it's the terminals. The CEM's are actually (electronics wise) very reliable.

The fact you have to keep jiggling the connections is an easy sign that this is the problem.

Volvo sell a terminal pack to strip and replace the wiring loom. They degrade over time and don't fit so well, hence intermittent issues.

Don't waste £700+ at Volvo for a new CEM, you'll be right back where you started since that's not the problem!

[SwissXC90]

Wow, that's what I get for trying to help people? Well, **** *** **

[FunkyMelon]

Originally Posted by SwissXC90

Wow, that's what I get for trying to help people? Well, **** *** **

If buy ' helping people' you mean pointing them towards the dealer with their wallet wide open for unnecessary expensive 'fixes' that will only put them hugely out of pocket with no fix then what did you expect?

[LizardOfBodom]

Originally Posted by Cornish Expat

...
Is there a permanent fix for a dodgy CEM or am I just going to have to dismantle everything and clean it every couple of months? If that’s the case then the car really isn’t fit for purpose as its going to have to be used for commuting soon.

Dont think of CEM as something you need to do maintenance on every so often - no, its either working OK or not. If not, its due to either connectors issue (loose or corroded etc) or internal problem (water ingress or just electronic dying). 99% of cases related to corroded/loose connections is sorted by cleaning and re-attaching all back into place, you dont need to repeat that every x months unless you have ongoing problem with passenger kicking the connectors or rain dripping from sunroof etc.
In extreme cases, as it happened, people had to replace CEM because of physical damage etc but even then I never heard of anybody going to dealership to do so especially if its gonna cost half of what your car is worth. You get a decent CEM from another donor car for pennies and send it to UK company to clone electronics for fraction of a price of new one. Agreed with FM on this one - dealership route especially in case of our double-digit old cars makes no sense in this case.
Same story with alternators and other parts, its just not worth doing some of the jobs in stealerships...

[Gadjit]

How much is the wiring loom?