B Series Truck 2WD 22L EFE Heater Component Diagram - 1990 Model
EFE Heater: Testing and Inspection
Checking Heater Continuity
PTC HEATER
1.
Disconnect the PTC heater connector.
2.
Connect an ohmmeter between the connector and the intake manifold, and verify continuity.
Heater Connector And Relay Schematic
PTC HEATER RELAY
1.
Apply battery power (positive to No. 1 terminal and ground No. 2 terminal), and verify continuity at terminals 3 and 4, using an ohmmeter.
Terminals
Power not applied
Power applied
3-4
No continuity
Continuity
