M1009 Alternator Light coming on

[Mike_Pop]

My Gen 1 light is on very faintly but my alternator is fine. It's so faint that I can only see the glow at night. Any reason for this? The belts are the right tightness as well.

I'm making a cross country trip and want to make sure I don't have any problems.

Thanks in advance!

 

[acetomatoco]

check for corrosion in the socket where the bulbs are.. also, check the output of the two alts and the connections at the bosch relay for the alt kickin. Take two spare batteries with you and a set of Nato jumpers with alligator clamps on one end...just in case..good insurance...also bring a jumper so you can run glow plugs if the card pukes...I use plier handles in an emergency.

 

[CCATLETT1984]

report back with the voltages that you get from each alternator.

 

[greybird]

CC is right... could be a weak alternator. Accurate voltages at the battery terminals will tell a lot of the story

 

[blowngn]

Also could be residual lighting making it's way from the main instrument cluster

 

[CCATLETT1984]

Re: RE: M1009 Alternator Light coming on

Also could be residual lighting making it's way from the main instrument cluster

NOPE, there is no way for light from the instrument cluster to get to that part of the dash, its very well seperated from the rest of the lights.

 

[blowngn]

RE: Re: RE: M1009 Alternator Light coming on

yea your right i looked at mine it is way to far! good lookout

 

[2deuce]

RE: Re: RE: M1009 Alternator Light coming on

My 1009 has done this in the past and the #1 light stays on much longer than #2 after it starts also. But it hasn't given me any trouble. The dull glow seems to come and go but #1 light never goes out until I rev the engine after startup.

 

[acetomatoco]

RE: Re: RE: M1009 Alternator Light coming on

The revving up allows the first alternator voltage to come up and then the 2nd alternator Bosch relay by your ashtray clicks and allows the voltage to be put in series to 28V or so... watch your voltmeter when the second light goes off... It depends on how good your batteries are, time of year (cold) etc...

 

[CCATLETT1984]

RE: Re: RE: M1009 Alternator Light coming on

I know that on my truck, a few others as well, that you need to blip the throttle a little, to get the 2nd alternator to "exicte" itself. since its almost impossible to have two alternators with the exact same turn-on points.

 

[Mike_Pop]

RE: Re: RE: M1009 Alternator Light coming on

I had my alternator tested and it is fluctuating in the amperage. My mechanic said it is probably a diode going bad. I'll pull it and have it fix it for me.

 

[gasser]

Re: RE: Re: RE: M1009 Alternator Light coming on

I know that on my truck, a few others as well, that you need to blip the throttle a little, to get the 2nd alternator to "exicte" itself. since its almost impossible to have two alternators with the exact same turn-on points.

Indeed ... This occurs with mine, and the other two "drivers" that I owned.

-graham

 

[Mike_Pop]

RE: Re: RE: Re: RE: M1009 Alternator Light coming on

I pulled my alternator and found that the positive battery post had burned on the inside of the alternator. It was an easy fix, a fifty cent bolt.

 

[CCATLETT1984]

RE: Re: RE: Re: RE: M1009 Alternator Light coming on

glad to hear that you got your issue resolved, let alone for such a cheap price.

 

[greybird]

RE: Re: RE: Re: RE: M1009 Alternator Light coming on

good find... NEVER IGNORE A SUBTLE HINT !!!

sub·tle /ˈsʌtl/ Pronunciation Key - Show Spelled Pronunciation[suht-l] Pronunciation Key - Show IPA Pronunciation
–adjective, -tler, -tlest.
1. thin, tenuous, or rarefied, as a fluid or an odor.
2. fine or delicate in meaning or intent; difficult to perceive or understand: subtle irony.