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        General >> Problems >> Cosworth Generator light glowing faintly
        
(Message started by: Cosray - The Hague - Holland on Aug 7th, 2006, 8:48pm)
Title: Cosworth Generator light glowing faintly
Post by Cosray - The Hague - Holland on Aug 7th, 2006, 8:48pm
Scorpio Cosworth V6 2.9i v24

Generator light on dash is glowing faintly for some months now.
At start it lights up brightly with all the other lights. Once engine runs it will stay stable and dim, only to be seen in tunnels or garage.
Battery power is fine, starting/running no probs.

a) What causes it? Generator diode broken?
b) What action is needed?

Curious, Ray
Title: Re: Cosworth Generator light glowing faintly
Post by RichardMS on Aug 7th, 2006, 9:23pm
I think it is the diode so you'll need a new or recon alternator.
Title: Re: Cosworth Generator light glowing faintly
Post by Atlantic_blue on Aug 7th, 2006, 9:38pm
Yes looks like a diode, you can  buy a diode pack & brushes if you want, & do it yourself if you can solder.
Title: Re: Cosworth Generator light glowing faintly
Post by hellblue on Aug 7th, 2006, 9:47pm
Read these first, charging problem....page  7 & cosworth R19 engine run relay....page  8     you may not be alone!  
Title: Re: Cosworth Generator light glowing faintly
Post by tintin on Aug 7th, 2006, 10:35pm
mine does this too sometimes, the bottom of the power steering reservoir is dripping slightly, runs down onto the alternator. only comes on when i've been 3-point turning etc, usually burns off after 10 mins or so. no adverse effects and its been doing it for 6 months... might just be this.

i know, i should tighten up the clip, but it is tiny amounts of fluid loss, havent had to top up yet  ;D

hth
Title: Re: Cosworth Generator light glowing faintly
Post by Paul_Boulden on Aug 8th, 2006, 8:47am
Hi Cosray,

I had a similar problem for several years on my 2.9 12 valve. It didn't seem to cause any problems and I assumed it was a failing diode pack.

Eventually I replaced the alternator after it failed suddenly, this made no  difference to the faintly glowing alternator / charging light. I removed relay R19 which stops the problem but closer investigation revealed damage to some wiring under the fusebox, I now have no air con. or heated front windscreen which both operate through this relay.

Your problem may be different but it would be worth checking R19 and the supply to it.

Paul
Title: Re: Cosworth Generator light glowing faintly
Post by Cosray - The Hague - Holland on Aug 8th, 2006, 1:09pm

on 08/07/06 at 21:47:27, hellblue wrote:
Read these first, charging problem....page  7 & cosworth R19 engine run relay....page  8     you may not be alone!  


Hi Hellblue, you've lost me here - I've looked for those pages on this website; found various on alternators but nothing on R19 save how to rebuild a fusebox.
Or - are referring to a manual of sorts?
Would you have a URL/link for me please?
Ray
Title: Re: Cosworth Generator light glowing faintly
Post by Cosray - The Hague - Holland on Aug 8th, 2006, 1:20pm

on 08/08/06 at 08:47:20, Paul_Boulden wrote:
Hi Cosray,

I had a similar problem for several years on my 2.9 12 valve. It didn't seem to cause any problems and I assumed it was a failing diode pack.

Eventually I replaced the alternator after it failed suddenly, this made no  difference to the faintly glowing alternator / charging light. I removed relay R19 which stops the problem but closer investigation revealed damage to some wiring under the fusebox, I now have no air con. or heated front windscreen which both operate through this relay.

Your problem may be different but it would be worth checking R19 and the supply to it.

Paul


I am not sure I want to risk losing any of those functions because of just a faint light on the dash.

R19 's description says 'Engine management system'. Why would relay that be a cause?

If the light glows in a stable way, which it does, then it suggests a small & constant differential voltage between battery to where it is connected. Where is the non-battery side connected to?

Another suggestion I got was to test if the light will extinguish when the alternator housing is connected to the car battery using a jump wire, to test if there is bad ground. Haven't had the time to do that yet. Is it worth while?

Ray
Title: Re: Cosworth Generator light glowing faintly
Post by hellblue on Aug 8th, 2006, 9:15pm
click on problems page @ top & bottom are page no. go to the pages i said you will see the problem titles as i said
Title: Re: Cosworth Generator light glowing faintly
Post by Dave2302 on Aug 13th, 2006, 4:27pm
Mine did this when I first got it and another alternator cured it.
Title: Re: Cosworth Generator light glowing faintly
Post by manscorpio on Aug 15th, 2006, 11:08pm
Just a thought on this quite common problem. If there are any auto-electricians out there what effect would there be if the wrong battery were fitted.  My problem first appeared when I had a new battery fitted.  I have since investigated the power of this new battery and find that it is rated at 60 Amps/hour.  My handbook says that the battery should be 63 Amps/hour.  Is it possible that the reduced capacity of the battery might upset the generator monitoring circuit and cause the light ot glow?
Title: Re: Cosworth Generator light glowing faintly
Post by Octavian_P on Aug 16th, 2006, 8:10am
Manscorpio, the answer is no, the battery in that case doesn't have a bad effect. On my 2.3 i have a 75 Ah battery....i never read the manual so i don't kind of care about the "recomandations". As for the generator it produces 90 A current in DOHC models and 100 A on cossworth. Also my 75 Ah battery has a current of 720 A....

So thinking from the electrical point of view

75 Ah is the electrical capacity of the battery...meaning it gives 75 A of current in an hour after which it goes flat

720A is the maximum current at a fast discharge...like cranking

A bettery to charge draws about 10 % of it's capacity, so for a 75 Ah battery a maximum current of 7.5 A is needed....

Knowing that the generator of the car produces 90 - 100 Amp...there should be absolutly no problem regarding the capacity of the battery.
Title: Re: Cosworth Generator light glowing faintly
Post by shionogi247 on Sep 6th, 2006, 12:41pm
Hi Cosray,

Laat je dynamo schoonmaken, er zit waarschijnlijk olie in vanweg een lek in een van de slangen van het reservoir van de stuurbekrachtiging!!! Ik had exact hetzelfde probleem, was voor 75 Euri geregeld, heb de dynamo self in- en uitgebouwd!

Groeten Hans

Sorry guys, I'm from Holland and so is Cosray, so I thought I could reply him in Dutch .. the problem is indeed oil dripping from the hoses, had the same problem! Alternator was cleaned and evrything worked fine, no more alternator light glowing on the dashboard!
Title: Re: Cosworth Generator light glowing faintly
Post by Cosray - The Hague - Holland on Sep 6th, 2006, 2:49pm
Thanks for your hint -- will follow up!
Ray


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