B4000 2WD V6-4.0L OHV (1994)
Engine Control Module: Testing and Inspection
1. Disconnect the Powertrain Control Module (PCM) connector.
Special Service Tool (SST) "Breakout Box"
2. Connect the Special Service Tool (SST) "Breakout Box" to the PCM.
3. Measure the voltage at each terminal with a voltmeter and compare the readings to "Normal" PCM Pin Voltages.
See: Specifications
4. If any PCM terminal voltage is incorrect, check the related input or output devices and wiring. If no problem is found, replace the PCM.
NOTE: All PCM Pin values may vary ± 20% depending on operating conditions. RPM values are axle ratio and tire size dependent.