Engine/Transmission (1998.5 - 2002) Electrical question/problem

[Just_George]

2001 2500, 109k miles



The other day, driving down the road and the 'check gauges' light comes on. The voltage gauge had zeroed... . shut it off at the next stop light, restarted, and everything seemed fine. Truck was fully warmed up at the time. However, I had noticed about 10 minutes earlier when starting (again, fully warmed up at this point) that the lights dimmed much as they do when the manifold heaters cycle. Since then, I've noticed another curious symptom - every time I start the truck, the voltage gauge initially reads 12v and slowly over about a 1 minute span rises to 14v.



My suspicion is that the alternator/voltage regulator are tired - I believe, but don't know for sure, that it is original. Looking for ideas and/or ways to verify before I diagnose 'with my wallet'. Not that a new alternator at 109k is a bad thing, but then again it might not solve the problem... .



Thanks in advance for any help.

 

[RonaldLarson]

The rising voltage indicates a charging alternator. Normal. It does sound like your battery terminals are very corroded. Clean them and the cable ends internals until they shine.

 

[klcammie]

2001 2500, 109k miles

The other day, driving down the road and the 'check gauges' light comes on. The voltage gauge had zeroed... . shut it off at the next stop light, restarted, and everything seemed fine. Truck was fully warmed up at the time. However, I had noticed about 10 minutes earlier when starting (again, fully warmed up at this point) that the lights dimmed much as they do when the manifold heaters cycle. Since then, I've noticed another curious symptom - every time I start the truck, the voltage gauge initially reads 12v and slowly over about a 1 minute span rises to 14v.

My suspicion is that the alternator/voltage regulator are tired - I believe, but don't know for sure, that it is original. Looking for ideas and/or ways to verify before I diagnose 'with my wallet'. Not that a new alternator at 109k is a bad thing, but then again it might not solve the problem... .

Thanks in advance for any help.

Anytime it is below 50 your heater grid will cycle on. When both are on your voltage will be 12v and go to 14v as the heaters turn off. this is what my does. I agree clean batt. terms and cables check all grounds you can find.