LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Chrysler >> 2001 >> Intrepid Base >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Self-Diagnostics >> Diagnostic Tests >> DTC P1494: Leak Detect Pump SW Or Mechanical Fault >> Testing
April 5, 2026: LEMON Manuals is launched! Read the announcement.

DTC P1494: Leak Detect Pump SW Or Mechanical Fault: Testing

  1. Turn ignition on. Using scan tool, read DTCs. If GOOD TRIP counter is displayed and equal to zero, go to next step. If GOOD TRIP counter is not displayed and equal to zero, go to step  7 .
  2. Turn ignition off. Disconnect engine vacuum supply hose at Leak Detection Pump (LDP). LDP is located on top of fuel tank. See Figure . Install a vacuum gauge to disconnected vacuum hose. Start engine and observe vacuum gauge. If vacuum is 13 in. Hg or more, go to next step. If vacuum is less than 13 in. Hg, repair vacuum leak or vacuum obstruction as necessary.
  3. Turn ignition off. Disconnect LDP harness connector. Turn ignition on. With scan tool in INPUTS/OUTPUTS, read LEAK DETECT PUMP SW state. Connect a jumper wire between battery voltage and LDP switch sense circuit (Orange/Red wire) at LDP harness connector. If LEAK DETECT PUMP SW state does not change, go to next step. If LEAK DETECT PUMP SW state changes, replace LDP.
  4. Turn ignition off. Remove jumper wire. Disconnect PCM harness connectors. See Figure . Measure resistance between ground and LDP switch sense circuit (Orange/Red wire) at LDP harness connector. If resistance is 5 ohms or more, go to next step. If resistance is less than 5 ohms, repair short to ground in Orange/Red wire between LDP and PCM.
  5. Measure resistance of LDP switch sense circuit (Orange/Red wire) between LDP harness connector and terminal No. 72 at PCM C2 harness connector. See Figure . If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open in Orange/Red wire.
  6. If no other possible causes are remaining, PCM is assumed to be defective. Replace PCM.
  7. Conditions that set DTC are not present at this time. Perform the following to help identify intermittent condition:
    • With engine running at normal operating temperature, wiggle related wiring harness while monitoring related parameters on scan tool. If voltage changes or DTC sets while wiggling wiring harness, repair connectors or wiring harness where wiggling caused voltage to change or DTC to set.
    • Review freeze frame information on scan tool. Duplicate conditions present when DTC was set.
    • Refer to any technical service bulletins that may apply.
    • Visually inspect related wiring harness. Check for chafed, pierced, pinched or partially broken wires.
    • Visually inspect related wiring harness connectors. Check for broken, bent, pushed out or corroded terminals.

    If a problem is found, repair as necessary. If no problems are found, test is complete.

scientia non olet · About LEMON Manuals