1985 Dodge Ram

Tiny
DANDREN
  • MEMBER
  • 1985 DODGE RAM
  • V8
  • 2WD
  • AUTOMATIC
  • 87,000 MILES
The headlight dashlights cargo light and radio all dim in and out while I am driving but are fine while I am parked and idleing. What could be the problem
Monday, March 23rd, 2009 AT 11:23 AM

2 Replies

Tiny
RASMATAZ
  • MECHANIC
  • 75,992 POSTS
Get your charging system checked out-The alternator could be on its way out or the battery is not taking it-get both load tested.
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Monday, March 23rd, 2009 AT 11:33 AM
Tiny
CARADIODOC
  • MECHANIC
  • 33,760 POSTS
Also check the battery cables. Watch the alternator gauge on the dash when this happens. If the needle drops when the lights dim, you could have worn brushes in the alternator. You have way too few miles to expect bad brushes already unless you drive in dusty conditions a lot. I can copy and paste the directions on testing this system. It's very easy, and this is a very reliable system. The brushes can often be replaced without removing the alternator from the engine.

While watching the brightness of the headlights, try wiggling the wiring harnesses under the hood while the engine is running. In particular, suspect corroded pins in connectors. Also, look at the voltage regulator on the firewall. It's about three by four inches, and 3/4" thick, and usually silver or black. It has a triangular connector with a blue and a green wire. Check the two mounting bolts to be sure they're tight. The mechanical connection is one of the electrical connections. The charging system will be dead if the regulator is not bolted solidly to the firewall.

Caradiodoc
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Wednesday, March 25th, 2009 AT 4:04 PM

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