Transmission Controls With PCM

Diagnostic Chart:

Wiring Diagram:

NO 2ND GEAR
During normal driving modes the PCM/TC adapts line pressure to prevent clutch slip and harsh shifts. If 2nd clutch is slipping after pressure is adapted to high line it is determined that 2nd gear is not available. Second gear clutch is applied by opening circuit 581 at the PCM.

DTC PARAMETERS
DTC 22 may be set while driving in 2nd (steady state) or during an up or downshift to 2nd, and when the PCM has detected the following conditions twice per ignition cycle.
^ Vehicle speed is above 5 km/b (3 mph).
^ Turbine speed greater than 224 rpm.
^ No turbine or vehicle speed diagnostic trouble codes or noise diagnostic trouble codes.
^ High line pressure has been commanded.
^ Ratio failure counter is equal to 255 steady state (counter range is 0-255) or shift counter is greater than 100 on a downshift or upshift.

TEST DESCRIPTION
Numbered steps below refer to numbered steps on chart.
1. Check for diagnostic trouble codes/information flags 14, 45, 46, 49, 68, 71, 72, 73, 74, 75, 76, 77, 78, 95, 97, 98, or 99. They must be eliminated first as a possible cause of DTC 22.
2. Check actuator operation. Use actuator quick check. The actuator quick check will Pulse Width Modulate (PWM) the actuators at a set rate. Listen and compare noise of 2nd gear actuator to that of other actuators. The noise of all should be similar.
3. Check pressure regulator valve operation. Use pressure test. Make sure pressure increases in correct increments during pressure test. If pressure is low, repair for pressure condition first.
4. Apply compressed air with rubber nozzle on air gun. This step will determine if there is an internal problem.
5. If there is a cross leak to another clutch, there may also be another code set indicating a gear stuck on. This may help pinpoint the source of the leak. If a leak is detected to lube circuit, check input nut torque.
6. As pressure is applied and released, the clutch plates should also apply and release. Observe oil holes in clutch housing. If oil has darkened and contains clutch plate material, the clutches have probably failed.

DIAGNOSTIC AIDS
^ When the PCM detects a fault in the circuit (open, ground, short), the PCM will open the circuit internally to protect the circuit.
^ Could be a hot or cold only condition. If condition is intermittent try to reproduce conditions in MALF table to reset the DTC.
^ If a DTC/information flag indicating 3rd or 4th gear is stuck on DTC 22 will also set. Repair the higher gear DTC/information flag first.
^ Possible wrong case or Fwd/Rev servo piston installed causing limited travel.