Tempo L4-122 2.0L DSL (1984)
Vehicle Speed Sensor: Testing and Inspection
Speed Signal Test
Speed signal test
Electronic Instrument Cluster Only
1.
With wheels raised and vehicle speed at 30 m.p.h., measure the AC voltage of the speed signal at the speed control amplifier connector, Fig. 10.
2.
If reading obtained is less than 6 volts, disconnect speed control amplifier and repeat measurement.
a. If voltage is greater than 6 volts, replace speed control amplifier and retest.
b. If voltage obtained is less than 6 volts, check circuit 150 back to speedometer stud on the cluster for an open or short. If circuit is satisfactory,
replace speedometer electronics and retest. If an open or short exists, repair as necessary.
3.
If reading obtained is more than 6 volts, measure the DC component at the speed control module.
a. If voltage obtained is greater than 1 volt, replace speedometer electronics and retest.
b. If voltage obtained is 1 volt, speedometer circuit is satisfactory. Proceed with ``Speed Control Diagnosis.''
