What do I check now Batt/alt reading good--on the display batt light come on and sometime stay on --but goes off before it can be check with tools.
Jun 6, 2022 at 2:51 AM
batt/alt ???
1999 FORD EXPEDITION
OPHYLLIS977
- MEMBER
- 1 POST
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There are a couple things that we need to cover first.
When you say that the battery and alternator read good, are you load testing each?
Here are guides that help with this:
https://www.2carpros.com/articles/car-battery-load-test
https://www.2carpros.com/articles/how-to-check-a-car-alternator
If they both check out ok using these tests, then we are going to need to catch this with the light on so that we can find out what the output voltage is of the alternator.
Plus, we are going to have to find out what the voltage is on the alternator at pin I. This is the charge indicator and there is a resistor in the cluster that may be causing the light to come on incorrectly.
Have you ever experienced a drained battery, or has it always operated correctly?
When you say that the battery and alternator read good, are you load testing each?
Here are guides that help with this:
https://www.2carpros.com/articles/car-battery-load-test
https://www.2carpros.com/articles/how-to-check-a-car-alternator
If they both check out ok using these tests, then we are going to need to catch this with the light on so that we can find out what the output voltage is of the alternator.
Plus, we are going to have to find out what the voltage is on the alternator at pin I. This is the charge indicator and there is a resistor in the cluster that may be causing the light to come on incorrectly.
Have you ever experienced a drained battery, or has it always operated correctly?
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Jun 7, 2022 at 12:57 AM
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