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Home >> Saab >> 2001 >> 9-5 Base, 4D Sedan, Standard >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Self-Diagnostics >> Fault Code Diagnosis >> P1240: Throttle Motor Circuit - Shorted >> Fault Isolation Procedure

Fault Isolation Procedure

  1. Checking the control module's flap motor output:
    • Turn the ignition switch to the ON position.
    • Contact ECM.
    • Some software does not support activation of Throttle Motor PWM Test (30 seconds); check to be sure it can be activated.
    If activation was possible, go to step  3, otherwise go to next step.

  2. Verifying the leads: Check the lead between pin 5 of the female throttle body connector and pin 48 of the control module, as well as between pin 10 of the female throttle body connector and pin 24 of the control module. If the Throttle Motor PWM Test (30 seconds) has not been run, and there are no faults in the leads, go to step  4. Otherwise, rectify any faults and go to step  5.
  3. Initiating diagnostics:
    • Activate: Throttle Motor PWM Test (30 seconds).
    • Follow the diagnostic tool's instructions.
    • Jiggle the leads and in-line connectors at several places and in different directions to reveal intermittent breaks and short circuits in the wiring harness. Observe the multimeter, test lamp or diagnostic tool while doing this.
    If the test lamp alternates between red and green, go to next step, otherwise go to step  2.
    4. NOTE: Next time the ignition switch is turned to the ON position the limp-home solenoid will be activated. The flap valve will then assume the mechanical limp-home position. It is therefore important to reset the limp-home mechanism AFTER all DTCs have been cleared.
  4. Changing components: Change the Throttle body. When finished, go to next step.
  5. Final check:
    • Turn the ignition switch to the ON position.
    • Clear the DTCs (ECM).
    • Turn the ignition switch to the OFF position.
    • Wait for 10 seconds.
    • Reset the limp-home mechanism.
    • Clear the DTCs in all systems.
    • Carry out a drive cycle: Drive the car at varying engine loads and engine RPM for 5 minutes.
    • Evaluate the drive cycle: Check that the DTC has not recurred.
    If the trouble code has recurred, the ECM is probably at fault and will need replacement. Replace with known-good ECM and retest. if no DTCs are present, then the steps taken to rectify the fault were correct.
Fig 1: Throttle Motor Circuit (4-Cyl)
G00207375Courtesy of SAAB-SCANIA OF AMERICA, INC.
Fig 2: Throttle Motor Circuit (V6)
G00207426Courtesy of SAAB-SCANIA OF AMERICA, INC.
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