Test N: Step 7

7) Check IDM Circuit For Short To VREF, GROUND & PIP  Turn key off. Install breakout box, leaving ECA disconnected. Disconnect EDIS module (if equipped). For shorts to ground, measure resistance between Test Pin No. 4 and test pins No. 16, 20, 40, 46 and 60.

On vehicles equipped with EDIS, a short to SIG RTN (Pin No. 46) may be indicated in conjunction with an actual PWR GND short when the 4-wire HEGO sensor is connected.

To test for shorts to VREF, measure resistance between test pins No. 36 and 26, at the breakout box.

To test for shorts to PIP, measure resistance between test pins No. 36 and 56, at the breakout box.

If each resistance is greater than 10 k/ohms, go to next step. If not, repair short circuit. Remove breakout box, reconnect all components and repeat QUICK TEST.