Temperature Gauge Test

CAUTION: DO NOT connect sender wire directly to ground during test.

Disconnect temperature sender wire from sending unit. Connect a 12-volt, 3.4-watt test bulb between connector terminal and ground. Turn ignition switch to ON position. Bulb should flash and temperature gauge needle should move. If test light does not flash and gauge needle does not move, repair wiring to sending unit.
If test light flashes and gauge needle moves, remove thermosensor (sending unit) from engine block and place sending unit in hot 158°F (70°C) water. Check sensor resistance with an ohmmeter. Thermosensor resistance should be 90-117 ohms at 158°F (70°C) on all models. Replace thermosensor if not operating within specification.
Remove the instrument cluster from the instrument panel. See appropriate INSTRUMENT CLUSTER under REMOVAL & INSTALLATION. Measure resistance between temperature gauge terminals at rear of cluster. See TEMPERATURE GAUGE RESISTANCE SPECIFICATIONS .

TEMPERATURE GAUGE RESISTANCE SPECIFICATIONS

Application

Terminals

Ohms

Colt, Colt 200, Summit ⁽¹⁾

B-D

144-174

C-D

68-82

B-C

76-92

Colt Vista ⁽²⁾

No. 1-No. 2

50-61

Colt Wagon ⁽³⁾

1-2

50-60

Ram-50 ⁽⁴⁾

7V-TU

49-61

⁽¹⁾	See Fig 1 or Fig 2 terminal location.

⁽²⁾	See Fig 3 terminal location.

⁽³⁾	See Fig 4 terminal location.

⁽⁴⁾	See Fig 5 terminal location.

Fig 1: Temp Gauge Resistance Check Terminals (Colt, Colt 200 & Summit W/Tachometer)

Courtesy of CHRYSLER MOTORS.

Fig 2: Temp Gauge Resistance Check Terminals (Colt, Colt 200 & Summit W/O Tachometer)

Courtesy of CHRYSLER MOTORS.

Fig 3: Temp Gauge Resistance Check Terminals (Colt Vista)

Courtesy of CHRYSLER MOTORS.

Fig 4: Temp Gauge Resistance Check Terminals (Colt Wagon)

Courtesy of CHRYSLER MOTORS.

Fig 5: Temp Gauge Resistance Check Terminals (Ram-50)

Courtesy of CHRYSLER MOTORS.

Fig 6: Identifying Voltmeter Resistance Test Terminals

Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.