Q: Has new alternator, new battery when started , motor dies when battery is disconnected...my mechanics are stumped on this

asked by on October 13, 2016

its a dodge 1986 b250 custom 19 ft long camper van, or title says body type MH wt 4500 its not charging the battery once battery s dead so is engine, replaced battery and alternator, the charging system includes a two battery system one for house and one for car it all looks factory installed, has a isilator an all.....you have any further ideas what might cause the power to not reach the batteries.. thank you thomas

My car has 72000 miles.
My car has an automatic transmission.

Instrument Voltage Regulator Replacement $207.87 - $439.61 Get a Quote

Hello.

If replacing those particular components did not correct the issue then the next thing I would look at is the vehicle’s voltage regulator. It appears that this engine’s electrical system is equipped with an external voltage regulator that functions, or malfunctions, independently of the alternator. The voltage regulator regulates power from the vehicle’s alternator, and can cause issues with the electrical system when it malfunctions. I would test it to see if it is functioning properly. It is a silver box that should be mounted somewhere in the engine bay, usually on a wheel well. A technician from YourMechanic can come to your home or office to replace your car’s voltage regulator if necessary.

Regards, Eduardo

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