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 > Dashboard Amp gauge reading high.

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Sunny Florida USA

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Joined: 09/04/2003

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Posted: 02/12/18 09:02pm Link  |  Quote  |  Print  |  Notify Moderator

I looked VR up for a 1990 B250 with 318 or 360 engine and both showed the flat firewall mounted solid state regulator we had on our 1970's B300 used.

In that van, there was a little VR on the back of the instrument cluster. I'd get erratic readings if it was bad, OR the ground connection was loose. Small metal-cased thing, not much bigger than the small automotive circuit breakers. If I became alarmed at rising Coolant Temp, I'd notice I also had More Gas and Higher Oil Pressure than just awhile ago. Knew it was time to work on the Cluster. I don't remember if the Ammeter was also affected.

If God's Your Co-Pilot Move Over, jd
2003 Jayco Escapade 31A on 2002 Ford E450 V10 4R100 218" WB


Near a large body of salty water

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Posted: 02/12/18 09:12pm Link  |  Quote  |  Print  |  Notify Moderator

Im well aware all the parts books list the widespread external mopar VRs that were used well before, but after 1988 on the 318 engines, and after 1989 for the 360 engine, all Dodge vans use a voltage regulator internal to the engine computer until they stopped making them in 2003.

The dashboard voltage regulator is seeking to hold 5 volts. The technology to hold this voltage is from the 1930's, and costs 37$ for a new one.

I instead installed a 3 amp Drok buck converter for under 7$.

I do not know if the stock dash ammeter is requiring this 5v source or not, Mine has been gone for many years now.




Joined: 06/27/2004

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Posted: 02/13/18 12:17am Link  |  Quote  |  Print  |  Notify Moderator

in my old 72 dodge
i installed a 5v flat pack regulator, heat sunk it to the dash, PN 7905?
cost 75 cents

i used Drock buck converter to fix the 12v regulation problem in 95 Safari DP
i also had to fix a ground problem with the dash board gauge panel

Radiate The Happy

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1997 F53 Bounder 36s


Ontario, Canada

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Posted: 02/15/18 03:32pm Link  |  Quote  |  Print  |  Notify Moderator

Took the van for a drive today and noticed that when I am stopped at a traffic light with the headlights and heater fan running full blast the needle would drop below 0 on the gauge but when I pulled away the needle would go back up above the 0 mark.
Also noticed the voltage gauge for the 2 house batteries was at only 12.32 after being plugged in for 3 days.

1990 L.E.R. Dodge B 250 Class B 17'


Moses Lake, WA

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Posted: 02/15/18 04:57pm Link  |  Quote  |  Print  |  Notify Moderator

I think you have found your problem! A Bad battery!

USAF Retired
Pace Arrow

2003 Chev Ice Road Tracker


las peƱas, michoacan, mexico

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Posted: 02/15/18 05:59pm Link  |  Quote  |  Print  |  Notify Moderator

Diagnostics with automobile dash gauges is like trying to diagnose pneumonia with a six-year old's Play Doctor plastic medic kit. Unreliable and vague would be a compliment.

My Doodge Spiritual's dashboard voltmeter says I have 12.5 volts running down the road and around 8 volts with the air conditioner and lights enabled. Of course the readings are absurdly in error. Perhaps on a par with one of those 8-Ball fortune telling toys.

I will list this for drill.

The work involves tapping into one of the three or four alternator stator to rectifier connections. Solder a stub, a connector, then run a single wire into the cab.

That wire gets connected to a standard Bosch relay. Right to one of the two magnetic coil connections. The other connection goes to chassis negative.

Ignition powered wire to the perpendicular power terminal of the relay

Exiting the CENTER terminal of the relay, another wire runs to the inlet of a warning lamp, an audio piezo alarm or both.

AC voltage from a stator connection to chassis negative is 8-volts. Enough to pull the relay contact points apart. This cuts the alarm circuit.

But if the alternator fails to charge and the ignition key is turned on, current will flow through the relay contacts and to whatever alarms are present. Naturally with the key turned off there is no power to the contacts.

Not only alerts the driver to a failed alternator but also to a thrown drive belt.

I've used this circuit successfully for decades.

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