I have a 2000 ford ranger 2.5L with an engine light and a P1401 fault code. At the advice of a parts store I replaced the egr valve sensor and the problem did not go away. I took voltage readings with a back probe at the sensor plug and found that all three wires were showing 5v. I understand that the reference wire should be the only one with 5v. I unplugged the connector and measures 5v on the reference and PCM signal wire. This means the PCM is pushing 5v through the signal wire. Should it be doing that? Could the PCM be bad and causing the egr valve sensor to short?