Pinpoint Test B: One-Touch Integrated Start (OTIS) Does Not Operate Correctly

Starting System

Pinpoint Test B: One-Touch Integrated Start (OTIS) Does Not Operate Correctly

Refer to Wiring Diagrams Set 20, Starting System for schematic and connector information. Electrical Diagrams

Normal Operation

The ignition switch is turned to the START position, the PCM receives a request to start the engine. Voltage is supplied through the start diode to the Transmission Range (TR) sensor and the PCM. With the gear selector in PARK or NEUTRAL, the TR (Transmission Range) sensor supplies voltage to the starter relay coil. Ground is supplied by the PCM causing the starter relay coil to energize and the starter relay contacts to close. This allows voltage to be supplied from Battery Junction Box (BJB) fuse 11 (30A) to the starter solenoid. The starter solenoid is grounded at the starter. Energizing the starter solenoid closes the solenoid contacts allowing voltage directly from the battery to the starter, engaging the starter drive into the ring gear causing the engine to crank and start. When the key is released the TR (Transmission Range) sensor no longer supplies voltage to the starter relay. The PCM supplies voltage to the starter relay to continue cranking for one touch start operation. The PCM disengages the starter once an engine rpm threshold is reached, a set crank time is exceeded or the ignition is turned OFF.

This pinpoint test is intended to diagnose the following:

- Wiring, terminals or connectors

- PCM

PINPOINT TEST B : OTIS (One-Touch Integrated Start) DOES NOT OPERATE CORRECTLY

B1 CHECK THE STATUS OF ONE-TOUCH START STATUS (OTS_STAT) PID

- Enter the following diagnostic mode on the scan tool: DataLogger- PCM.

- Monitor the OTS_STAT PID with the ignition switch in the RUN position.

Is the One-Touch Integrated Start (OTIS)
PID enabled?

Yes
GO to B2.

No
ENABLE OTIS (One-Touch Integrated Start). TEST the system for normal operation. If OTIS (One-Touch Integrated Start) will not enable, INSTALL a new PCM. TEST the system for normal operation.

B2 CHECK THE STARTER MOTOR CONTROL OUTPUT DETECTED (SMC_MON) PID

- Enter the following diagnostic mode on the scan tool: DataLogger- PCM.

- Monitor the SMC_MON PID with the ignition switch in the START position.

Does the PID change from OFF to ON?

Yes
INSTALL a new PCM. TEST the system for normal operation.

No
REPAIR circuit 50-BB15 (GY/OG) for an open between the start diode and PCM. TEST the system for normal operation.