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Alternators again. I hate em.
- bennyboy
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Does the 5th have that large doofa plug that goes in to the alternator? If so, has the small clip on it broken?
Clutching at straws a bit, but the same happened on mine and it would be fine for a day or two, then everything would drop and the warning lights would come on - it was just that the large plug was working it's way loose with engine vibration.
If yours is the same, it could be that it's not actually getting to charge the thing properly etc.
Clutching at straws a bit, but the same happened on mine and it would be fine for a day or two, then everything would drop and the warning lights would come on - it was just that the large plug was working it's way loose with engine vibration.
If yours is the same, it could be that it's not actually getting to charge the thing properly etc.
- RattyMcClelland
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I hate this.
So i tested the voltage on the new alternator and at idle its at 14.2v at the alt and 14v at the battery. When fully loaded up electrically and reved it drops to 13.6v and but never goes above 14v.
I did all the wiring tests according to the manual and it all indicates the alternator is at fault.
I have just got a spare used OEM alternator that is know as working. Fitted it and again its charges fine but the battery light is still on.
WTF..
I have reground everything. Absolutely no other electrical faults apart from ATTS and airbag light as usual.
All i can try next is the ELD or the multiplexer. I cannot find the drivers side multiplexer at all.
Unless both alternators are at fault.
So i tested the voltage on the new alternator and at idle its at 14.2v at the alt and 14v at the battery. When fully loaded up electrically and reved it drops to 13.6v and but never goes above 14v.
I did all the wiring tests according to the manual and it all indicates the alternator is at fault.
I have just got a spare used OEM alternator that is know as working. Fitted it and again its charges fine but the battery light is still on.
WTF..
I have reground everything. Absolutely no other electrical faults apart from ATTS and airbag light as usual.
All i can try next is the ELD or the multiplexer. I cannot find the drivers side multiplexer at all.
Unless both alternators are at fault.


- mercutio
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did you get a 100 amp alternator?
bristol_bb4 wrote:ahhh a 5th gen, i love 5th gens![]()
Dino wrote:I loves the 5th gen really.... just dont quote me on it...
4thgenphil wrote:Mines 4 1/4 unches mate, sorry
http://www.ludegeneration.co.uk/profile ... -t618.html
- RattyMcClelland
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- mercutio
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no the oem one what was it off? i bet it wasnt a type S your car needs more voltage your ecu knows how much it needs if it isnt getting it, it throws the lights.
You either need to change the ecu or get an alternator that is producing enough.
You either need to change the ecu or get an alternator that is producing enough.
bristol_bb4 wrote:ahhh a 5th gen, i love 5th gens![]()
Dino wrote:I loves the 5th gen really.... just dont quote me on it...
4thgenphil wrote:Mines 4 1/4 unches mate, sorry
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- RattyMcClelland
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It was off a uk vti. The Type S uses the exact same alternator. Same part number. I can't see why one ecu needs different voltage to another.mercutio wrote:no the oem one what was it off? i bet it wasnt a type S your car needs more voltage your ecu knows how much it needs if it isnt getting it, it throws the lights.
You either need to change the ecu or get an alternator that is producing enough.
Maybe I'm lucky and got crappt voltage regulators in all my alts.

- mercutio
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all that i know is that i matched the part number on my old alternator and got one with the equivalent number in 100 amp form no problem anymore all the alternators before that kept the light on and still charged.
bristol_bb4 wrote:ahhh a 5th gen, i love 5th gens![]()
Dino wrote:I loves the 5th gen really.... just dont quote me on it...
4thgenphil wrote:Mines 4 1/4 unches mate, sorry
http://www.ludegeneration.co.uk/profile ... -t618.html
- wurlycorner
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So your current one is a Denso CJV72 90amp?
http://www.lingshondaparts.com/honda_ca ... k_03=23389
Which has lots of cross-compatible honda part numbers;
http://infopart.org/lucas-electrical-lra02122-part
Depends how much you want to spend, but if you want a good quality high output one... Try these guys?;
http://www.brise.co.uk/Denso/
http://www.lingshondaparts.com/honda_ca ... k_03=23389
Which has lots of cross-compatible honda part numbers;
http://infopart.org/lucas-electrical-lra02122-part
Depends how much you want to spend, but if you want a good quality high output one... Try these guys?;
http://www.brise.co.uk/Denso/
--
Iain.
Iain.
Super Secret 1G (not really super secret!)
- RattyMcClelland
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So the one in the car is a completely original CJU72 from a 5th Gen UK VTI. Charges and works but light still on.
CJU75 seem to be 5th Gens up to 99 spec. Then 99spec onwards and the Type S seem to be CJV72
They have different part numbers but 1 number and it seems the rotor assembely is the difference. Could that really make the difference?
However the recon alt that i have is a Delco Remy DRA0461 which cross refences with the CJV72 but is a 90amp alternator.
NOW THEN.........................................
On this site.
The one Wurly linked
The 97-99 alternator 31100-P5M-G01 is a 90amp alternator
The 99-01 alternator 31100-P5M-G02 is a 100amp alternator
So could it really be that the amps is making all the difference.......just like Mercutio said....
So ill try a 100amp version...and post back the results.
CJU75 seem to be 5th Gens up to 99 spec. Then 99spec onwards and the Type S seem to be CJV72
They have different part numbers but 1 number and it seems the rotor assembely is the difference. Could that really make the difference?
However the recon alt that i have is a Delco Remy DRA0461 which cross refences with the CJV72 but is a 90amp alternator.
NOW THEN.........................................
On this site.
The one Wurly linked
The 97-99 alternator 31100-P5M-G01 is a 90amp alternator
The 99-01 alternator 31100-P5M-G02 is a 100amp alternator
So could it really be that the amps is making all the difference.......just like Mercutio said....

So ill try a 100amp version...and post back the results.
