Wine Country mopar

Tel: 415-472-3817

P.O. BOX 97 Cotati CA 94931


TIP: Eliminating the "weakness" in the 1975 and earlier MOPAR thru the bulkhead charging / ammeter circuits

 Tips & Tricks Submitted by Our Members

This is a picture of the MOPAR special tool for checking fuel, oil, and temperature gauges in vintage Chrysler cars.  If you put a DVM on the tool leads the resistance values  indicated  at “L”, “M”, and “H” were:

L = 73.7 Ohms (empty)
M = 23.0 Ohms (1/2)
H = 10.2 Ohms (full)

To build a home  brew version of the special gauge testing tool follow the schematic shown above. 
When testing, the assumption is that the gauge is properly supplied by a working voltage limiter at 5V

TIP: Link to technical articles at the Imperial Club's Website

Once this modification has been made, the ammeter will no longer be accurate as the ammeter circuit is no longer carying the charging system load. In my case, I added a voltmeter to monitor the condition of the charging circuit. Modern MOPAR cars now use voltmeters in place of ammeters. The existing ammeter must remain in circuit as the interior accessories of the car are fed from it.

TIP: How to make  a "special tool" for checking your MOPAR's gauges