VSA DTC Troubleshooting: 66
  1. Measure the voltage between ECM connector A (44P) terminal No. 40 and body ground.
Is there battery voltage when the brake pedal is pressed?
YES -
Check for loose terminals in the ECM connector A (44P). If necessary, substitute a known-good ECM and retest. ■
NO -
Repair open in the wire between the ECM and the brake pedal position switch.■
  1. Turn the ignition switch ON (II).
  1. Clear the DTC with the HDS.
  1. Press the brake pedal several times.
  1. Check for DTCs with the HDS.
Is DTC 66 indicated?
YES -
Go to Step 17 .
NO -
Intermittent failure, the system is OK at this time. Check for loose terminals between the brake pedal position switch 4P connector, the ECM connector A (44P), and the VSA modulator-control unit 46P connector. Refer to intermittent failures troubleshooting. ■
  1. Check the BRK PRESS in the VSA DATA LIST with the HDS while moving the brake pedal.
Does the pressure increase when the pedal is pressed, and decrease when the pedal is released?
YES -
Check for loose terminals in the VSA modulator-control unit 46P connector. If necessary, substitute a known-good VSA modulator-control unit and retest.■
NO -
Check for brake hose and line damage, and repair the hose or the line. ■