Pinpoint Test B: OTIS Does Not Operate Correctly (Automatic Transmission Only)
Starting System
Pinpoint Tests
Pinpoint Test B: One-Touch Integrated Start (OTIS) Does Not Operate Correctly (Automatic Transmission Only)
Refer to Wiring Diagram Set 20, Starting System for schematic and connector information. Diagrams By Number
Normal Operation - Automatic Transmission
Under normal operation of an automatic transmission equipped vehicle, when the ignition switch is turned to the START position and released, the PCM receives a starter motor request signal through circuit CDC35 (BU/WH), power is then supplied to the starter relay through circuit CDC38 (WH/VT) from the PCM. The PCM will receive a signal from the Transmission Control Module (TCM) that the vehicle is in PARK or NEUTRAL through circuit CET21 (GN/WH). A ground is supplied through circuit CDC12 (YE) from the PCM causing the starter relay coil to energize and the relay contacts close. This allows power to be supplied from Battery Junction Box (BJB) fuse 40 (30A) to the relay contacts which then flows through circuit CDC25 (BN/GN) to the starter solenoid. The solenoid is grounded at the starter motor. Energizing the starter solenoid will engage the starter drive into the ring gear and closes the solenoid contacts allowing power directly from the battery through circuit SDC02 (RD) to the starter motor to start the engine. The PCM will disengage the starter motor based on engine running (rpm threshold), a set crank time has been exceeded or the ignition switch has been turned to the OFF position.
This pinpoint test is intended to diagnose the following:
- Circuitry
- PCM
PINPOINT TEST B: ONE-TOUCH INTEGRATED START (OTIS) DOES NOT OPERATE CORRECTLY (AUTOMATIC TRANSMISSION ONLY)
-------------------------------------------------
B1 CHECK THE STATUS OF THE PCM 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 PID enabled?
Yes
GO to B2.
No
ENABLE One-Touch Integrated Start (OTIS). TEST the system for normal operation. If OTIS will not enable, DIAGNOSE the PCM. REFER to Computers and Control Systems Information.
-------------------------------------------------
B2 CHECK THE PCM KEY POSITION FOR START INDICATED (START_KEY) PID
- Monitor the START_KEY PID while cycling the ignition switch from the OFF to START position.
- Does the PID change from OFF to ON?
Yes
GO to B4.
No
GO to B3.
-------------------------------------------------
B3 CHECK THE PCM TR SENSOR PID
- While observing the Transmission Range (TR) sensor PID, place the vehicle in PARK and NEUTRAL.
- Does the PID match the gear selection?
Yes
GO to B4.
No
GO to the appropriate automatic transmission system to diagnose the TR sensor.
-------------------------------------------------
B4 CHECK CIRCUIT CDC35 (BU/WH) FOR AN OPEN
- Disconnect: Start Diode .
- Disconnect: PCM C1232B .
- Measure the resistance between BJB start diode cavity-1, circuit CDC35 (BU/WH) and PCM C1232B-26, circuit CDC35 (BU/WH), harness side.
- Is the resistance less than 5 ohms?
Yes
GO to B5.
No
REPAIR the circuit CDC35 (BU/WH). TEST the system for normal operation.
-------------------------------------------------
B5 CHECK CIRCUIT CDC38 (WH/VT) FOR AN OPEN
- Disconnect: Starter Relay .
- Measure the resistance between BJB start diode cavity-2, circuit CDC38 (WH/VT) and PCM C1232B-39, circuit CDC38 (WH/VT), harness side and BJB starter relay cavity-85, circuit CDC38 (WH/VT) and PCM C1232B-39, circuit CDC38 (WH/VT), harness side.
- Are the resistances less than 5 ohms?
Yes
DIAGNOSE the PCM. REFER to Computers and Control Systems Information.
No
REPAIR the circuit CDC38 (WH/VT). TEST the system for normal operation.
-------------------------------------------------