dash lights need help before thursday!

[89gqpatrol4x4]

I'm going to straddie on friday and the misses came home tonight and the water in feul light and the battery light are on but only faintley, they dissapear when i rev the engine. I have drained the feul filter (I think) according to the original owners manuel but the lights are still on. Could this be caused by they altenator not charging properly or something else. Any help would be grately appreciated as I don't want to get stuck on stradbroke island! (as nice as that sounds, I have bills to pay, so need to go back to work LOL)

[threedogs]

Could it be your alternator as when you rev the lights go out???
Put a multi meter on the battery when going should read 13.8 with the revs up

[89gqpatrol4x4]

Could it be your alternator as when you rev the lights go out???
Put a multi meter on the battery when going should read 13.8 with the revs up

getting a loan of a multimeter tommorrow so will see what that says

[happygu]

Definitely sounds like the alternator is on the way out.

Mic

[johno90]

Something i have found with both of my gq's is that for some reason, age, dirt, etc. it gets massive voltage drop to the cabin circuit on the earth side. i thought my alt was screwed but when i checked the battery it was good and voltage gauge in cluster was good as i reads off a different curcit to the dash itself. All i did was use some amp cable and ran it throughout the firewall to a nice metal bracket and then to neg terminal and bam everything was mint. Thats just saying if you alt tests mint.