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Home >> Dodge and Ram >> 1998 >> Durango 5.9 Z, Part Time >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Tests W/Codes - Engine Performance >> Self-Diagnostic Tests >> Test TC-21A: Injector Control Circuits
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Test TC-21A: Injector Control Circuits

NOTE: For connector terminal identification, see CONNECTOR IDENTIFICATION . For component location and wiring diagram, see WIRING DIAGRAMS article.
  1. Start engine and allow to idle for at least 20 seconds. Turn engine off. Turn ignition on, engine off. DO NOT restart engine. Go to next step.
  2. Using scan tool, read DTCs. If scan tool displays any INJECTOR CONTROL CIRCUIT with a start run count of zero, perform appropriate test. See INJECTOR CONTROL CIRCUIT TESTS  table. If scan tool does not display any INJECTOR CONTROL CIRCUIT with a start run count of zero, go to next step.
    INJECTOR CONTROL CIRCUIT TESTS

    Scan Tool Display Test
    INJECTOR #1 CONTROL CIRCUIT TC-21B
    INJECTOR #2 CONTROL CIRCUIT TC-20A
    INJECTOR #3 CONTROL CIRCUIT TC-19A
    INJECTOR #4 CONTROL CIRCUIT TC-61A
    INJECTOR #5 CONTROL CIRCUIT TC-69A
    INJECTOR #6 CONTROL CIRCUIT TC-70A
    INJECTOR #7 CONTROL CIRCUIT TC-79A
    INJECTOR #8 CONTROL CIRCUIT TC-80A
    INJECTOR #9 CONTROL CIRCUIT TC-55A
    INJECTOR #10 CONTROL CIRCUIT TC-56A
  3. Condition required to set DTC is not present at this time. INJECTOR CONTROL CIRCUIT DTC is set if no inductive activation is sensed by Powertrain Control Module (PCM) after injector turns off, and with no other injectors on. Possible causes are: open or shorted injector wiring, defective Auto Shutdown (ASD) relay wiring circuit to injector, defective connections, open injector or defective PCM. Go to next step.
  4. Check for defective wiring and connections at injectors, ASD relay and PCM. Repair wiring and connectors as necessary and perform TEST VER-2A: ROAD TEST VERIFICATION . If wiring and connectors are okay, go to next step.
  5. Start engine. Wiggle wiring harness from injectors to PCM. If engine misfires or stalls, repair wiring harness as necessary and perform TEST VER-2A: ROAD TEST VERIFICATION . If engine does not misfire or stall, see INACTIVE DTC CONDITION . Test is complete. Perform TEST VER-2A: ROAD TEST VERIFICATION .