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I have a 99 gmc truck 4.3 I lost power to my alternator hot…

Customer Question
I have a 99...

I have a 99 gmc truck 4.3 I lost power to my alternator hot lead and car won't start from switch

Mechanic's Assistant: Is the power loss consistent, or does it fluctuate?

Constant

Mechanic's Assistant: What is the model of your '99 GMC?

Ist consistent and my granny seams like it's taking off in 3rd gear

Mechanic's Assistant: Are you fixing your vehicle yourself? What have you tried so far?

I have tried switching the relays and checking all fuses

Submitted: 22 days ago.Category: GMC
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Answered in 1 minute by:
3/30/2018
GMC Mechanic: JFN1, ASE Certified Technician replied 22 days ago
JFN1
JFN1, ASE Certified Technician
Category: GMC
Satisfied Customers: 5,628
Experience: GM Master Technician
Verified

There is no power at the large terminal on the back of the alternator, is that what you're saying?

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Gm Tech (Cam)
Gm Tech (Cam)
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