1994 Oldsmobile Cutlass Ciera Cruiser V6-3100 3.1L MFI VIN M
Vehicle Level Powertrain Management Computers and Control Systems Testing and Inspection Diagnostic Trouble Code Tests and Associated Procedures P Code Charts P1650
The Powertrain Control Module (PCM) is used to control several components such as those illustrated above. The PCM controls these devices through the use of a Quad-Driver Module (QDM) . When the PCM is commanding a component "ON," the voltage potential of the output circuit will be "low" (near 0 volts). When the PCM is commanding the output circuit to a component "OFF," the voltage potential of the circuit will be "high" (near battery voltage). The primary function of the QDM is to supply the ground for the component being controlled.
Each QDM has a fault line which is monitored by the PCM. The fault line signal is available on the data stream for scan tool test equipment display on Tech 1. The PCM will compare the voltage at the QDM based on accepted values of the fault line. If the QDM B fault detection circuit senses a voltage other than the accepted value, the fault line will go from a "low" signal on the data stream to a "high" signal and Diagnostic Trouble Code P1650 will set.
DIAGNOSTIC TROUBLE CODE (DTC) P1650 WILL SET WHEN
The engine is running.
The PCM detects an improper voltage level on a circuit connected to QDM B.
The above conditions met for 5 seconds.
ACTION TAKEN (PCM WILL DEFAULT TO)
The PCM will illuminate the Malfunction Indicator Lamp (MIL) (Service Engine Soon) with a current DTC P1650 set. QDM B controls transmission shift solenoid A and B, Torque Converter Clutch (TCC) Pulse Width Modulated solenoid and three Exhaust Gas Recirculation (EGR) solenoids.
DTC CHART TEST DESCRIPTION
Number(s) below refer to circled number(s) on the diagnostic chart.
If a QDM related DTC is stored, diagnose that DTC first. The repair made to the related DTC will repair DTC P1650 also.
This test will determine which QDM B control device has failed.
Monitor the voltage at each terminal shown above while moving related harness connectors, including PCM harness. If the failure is induced, the voltage will change. This may help locate an intermittent condition. Check for bent pins at PCM and PCM connector terminals. If DTC reoccurs with no apparent connector problem, replace PCM.
PCM is protected by an internal circuit breaker.
PCM replacement is not necessary after repairing QDM B Quad driver controlled circuit or component.