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Home >> Kia >> 2003 >> Rio Base, Automatic >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Self-Diagnostics >> Diagnostic Tests >> DTC P0501: Vehicle Speed Sensor Circuit Malfunction >> Test Procedure
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Test Procedure

  1. Turn ignition off. Connect Hi-Scan Pro/Kia Data Pro Scan tool or equivalent to OBD-II Data Link Connector. See Figure . Turn ignition on. Monitor for right front WSS output voltage. Voltage should be battery voltage with ignition on and 0-battery voltage while driving. If voltage is as specified, problem is intermittent. Check right front WSS and ECM for proper harness connection. Go to step  5 . If voltage is not as specified, go to next step.
  2. Turn ignition off. Disconnect ECM harness connector "B02". See Figure and right front Wheel Speed Sensor (WSS) 2-pin harness connector. See Fig 1 . Measure resistance between right frontWSS connector terminal No. 1 (Light Green/Red wire) and ECM connector terminal B02-12. Also measure resistance between right frontWSS connector terminal No. 2 (Light Green/Yellow wire) and ECM connector terminal B02-18. Both resistances should be below one ohm. If resistances are as specified, go to next step. If any resistance is not as specified, repair open or short circuit as necessary. Go step  5 .
  3. With ECM and right front WSS harness connector disconnected. Measure resistance between ground and WSS connector terminal No. 2 (Light Green/ Yellow wire). Resistance should be infinite. If resistance is as specified, go to next step. If resistance is not as specified, repair short circuit as necessary. Go step  5 .
  4. Return vehicle to original condition. Backprobe and measure voltage at right front WSS connector terminal No. 2 (Light Green/ Yellow wire). Voltage should be battery voltage with ignition on and 0-battery voltage while driving. If voltage is as specified, check for intermittent poor terminals contacts due to oxidation, bent, deformed or misplaced at WSS and ECM connectors. Repair or replace as necessary. Go to next step. If voltage is not as specified, temporarily install a known good WSS and check for proper operation. If problem is corrected, replace WSS. Go to next step.
  5. After repair, return vehicle to original condition. Clear codes using Hi-Scan Pro/Kia Data Pro Scan tool or equivalent. Verify repairs by driving vehicle and monitoring for pending codes. If DTC is set during test drive, follow appropriate DTC test procedure.
Fig 1: Identifying Front Wheel Speed Sensor Connector Terminals
G00038206Courtesy of KIA MOTORS AMERICA, INC.
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