P0613

P0613-INTERNAL TCM

Theory of Operation
The internal Watchdog (WD) is a separate hardware circuit that continuously monitors the microprocessor. To insure the proper operation of the Transmission controller the watchdog must receive a signal from the microprocessor within a specific time window (14 msec � 1 msec) to prevent a system shutdown after a short delay (570 msec). The microprocessor periodically tests the WD's ability to provide this shutdown function using a three phase test;
1) Send the signal too late > 15 msec
2) Send the signal too early < 13 msec
3) Delay test < 590 msec

If the watchdog input signal arrives too early or too late, the Watchdog Fault line will go low and the watchdog delay will start to time out. The delay will be reset by the correct timing of watchdog signal sent during subsequent operations.

The Delay Test checks the delay time out. The Delay Monitor line is pulled low, which forces the delay to start timing out. At the end of the delay time the Transmission Relay will be turned off. The delay test, upon detection of the relay turning off, will immediately turn the relay back on before shutdown can occur.

- When Monitored:
1) One time after the controller is reset (ignition turned to the RUN position) and every 60 seconds thereafter. The Delay Test is executed after a reset only.
2) 2 seconds after an invalid test.
- Set Condition:
If either of the following conditions occur 3 times:
1) The watchdog fault line remains high after the period has elapsed for the too early - too late watchdog test.
2) The Transmission Control Relay remains on after the watchdog delay expired.

Possible Causes
POWER OR GROUND CIRCUIT
POWERTRAIN CONTROL MODULE

Always perform the Pre-Diagnostic Trouble shooting procedure before proceeding. Testing and Inspection

Diagnostic Test
1. CHECK THE WIRING AND CONNECTORS
Using the schematics as a guide, check the Powertrain Control Module (PCM) terminals for corrosion, damage, or terminal push out. Pay particular attention to all power and ground circuits.

NOTE: Due to the integration of the Powertrain and Transmission Control Modules, the transmission part of the PCM has it's own specific power and ground circuits. Wiggle the wires while checking for shorted and open circuits. Check for any Service Bulletins that may apply.

Were there any problems found?
Yes >> Repair the power and/or ground circuits as necessary Perform 45RFE/545RFE TRANSMISSION VERIFICATION TEST - VER 1. Verification Tests
No >> Replace the PCM. With the scan tool, perform QUICK LEARN. Perform 45RFE/545RFE TRANSMISSION VERIFICATION TEST - VER 1. Verification Tests