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Test Y - Isolation Valve Control

  1. Turn ignition off. Ensure Modulator Valve (PMV) Black C1 connector is properly connected. Disconnect EBCM/EBTCM connector. Connect Pinout Box (J-38716). Disconnect main relay.
  2. Measure resistance between pinout box pins No. 3 and 37 (left isolation valve). See Figure . Resistance should be less than 10 ohms. If resistance is not as specified, check and repair open in circuit No. 1657 (Orange wire).
  3. Measure resistance between pinout box pins No. 3 and 40 (right isolation valve). Resistance should be less than 10 ohms. If resistance is not as specified, check and repair open in circuit No. 1658 (Purple wire).
  4. Measure resistance between ground and pinout box pin No. 37 (left isolation valve). Resistance should be more than 5 ohms. If resistance is not as specified, check and repair short to ground in circuit No. 1657 (Orange wire).
  5. Measure resistance between ground and pinout box pin No. 40 (right isolation valve). Resistance should be more than 5 ohms. If resistance is not as specified, check and repair short to ground in circuit No. 1658 (Purple wire).
  6. If all measurements are as specified, check EBCM/EBTCM connector terminals for poor contact. If EBCM/EBTCM terminals are okay, replace EBCM/EBTCM. After all repairs are complete, clear codes, and repeat ABS/TCS functional check. See Figure .
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