Another Battery Light Question (sorry)

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nick0789

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2005 Z71 tahoe, about 186k miles. Bone stock.

Twice in the past week when I start my Tahoe from a cold start, my battery light comes on and stays on during driving. The gauge in the instrument cluster appears fine, given that it bounces around a little anyways thanks to the on-demand charging system. Battery is less than a year old (ACDelco Gold), and alternator is about 5 years old (NAPA; new mfg).

- Voltage at the battery reads ~ 14.4V-14.6V depending on when the charging system wants to kick on.
- Voltage at the 10A ignition fuse under the hood is reading 14.4V (within 0.05V of the battery)
- Voltage at the instrument cluster’s pink wire (B9 I think) is also reading 14.4V

Any ideas on what I can troubleshoot, or am I dealing with an intermittent cluster issue?

Thanks in advance and sorry for yet another battery light question.
 

Jimmyy

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Lots of post on here talking about the grounds on these vehicles causing intermittent electrical issues.
 

swathdiver

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2005 Z71 tahoe, about 186k miles. Bone stock.

Twice in the past week when I start my Tahoe from a cold start, my battery light comes on and stays on during driving. The gauge in the instrument cluster appears fine, given that it bounces around a little anyways thanks to the on-demand charging system. Battery is less than a year old (ACDelco Gold), and alternator is about 5 years old (NAPA; new mfg).

- Voltage at the battery reads ~ 14.4V-14.6V depending on when the charging system wants to kick on.
- Voltage at the 10A ignition fuse under the hood is reading 14.4V (within 0.05V of the battery)
- Voltage at the instrument cluster’s pink wire (B9 I think) is also reading 14.4V

Any ideas on what I can troubleshoot, or am I dealing with an intermittent cluster issue?

Thanks in advance and sorry for yet another battery light question.
The light usually refers to the charging system aka the alternator. There may be internal codes stored that can be pulled with a Tech-2 and a replay/snapshot of the sensors at the time the code was set.
 

blueinkd

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A while back my battery light was on due to a bad alternator. I took it to Autozone and the thing still passed on the bench. I replaced it anyways with a NEW Duralast unit and problem solved. It all started when my main *Lady got stranded at work with a no crank condition.
 

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