1.8L '86 Jetta not charging the battery

How have you tested the battery and the alternator? How do you know the battery is not being charged?

What is the voltage at the battery with engine on and with engine running?

Are you getting voltage to the battery's little wire when the ignition is turned on? I will ASSuME that you are not getting the battery light coming on in the dash when you first turn the ign on. All ground wires/cables to the engine/transmission and body clean & tight?

Might be a bad LED in the dash. You can get to it when you remove the gauge cluster which is not hard to do. ;-)

later, dave (One out of many daves)

The led has little to no function in the exciter circuit it's just an indicator. The alternator gets it's exciter voltage via a 150ohm (1W)resistor on the back of the instr.panel.

Remove positive clamp from the battery and place a amp meter between battery

• and clamp. There should be hardly no current flowing. If it's above let say 100mA then it would drain the battery in a few days. If there's a big current flowing >1amp try disconnecting the alternator. Could be that you have a short in one of the diodes.

SFC

"dave AKA vwdoc1" schreef in bericht news:0gwKf.35749$F snipped-for-privacy@newssvr29.news.prodigy.net...

Does his LED light come on ever? Hmmm I seem to remember one watercooled VW I worked on that had a charging problem. How does that LED light function? Maybe I changed more than that LED light and got it working again. Oh well time gets away! lol AFAIK A small drain while the engine was off would not stop an alternator from charging nor that LED light from not lighting unless the alternator was defective or something else was wrong. Thanks SFC! later, dave (One out of many daves still learning)