LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Suzuki >> 2007 >> XL7 Limited, FWD >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Engine General Information And Diagnosis >> Diagnostic Information and Procedures >> DTC P0642 or P0643 >> Circuit/System Testing
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Circuit/System Testing

NOTE: Additional DTCs will set when disconnecting the components.
  1. Ignition OFF, disconnect the harness connector of all appropriate sensors for the applicable DTC. Refer to DIAGNOSTIC AIDS .
  2. Ignition ON, measure for 4.6-5.2 volts between one of the 5-volt reference circuits and ground.
    • If the voltage is less than 4.6 volts, test for a short to ground on all the 5-volt reference circuits. If all circuits test normal, replace the control module.
    • If the voltage is greater than 5.2 volts, test for a short to voltage on all the 5-volt reference circuits for each component associated with the appropriate 5-volt reference circuit. If all circuits test normal, replace the control module.
      NOTE: A short to voltage on the signal circuit of certain components may cause this DTC to set.
  3. Connect each component associated with the 5-volt reference 1 circuit one at a time while monitoring the 5-Volt Reference 1 Circuit Status parameter with a scan tool. The parameter should continue to display OK.
    • If the parameter displays Fault when a component is connected, test the signal circuit of that component for a short to voltage. If the circuit tests normal, replace the component.