Vehicle Does Not Decelerate By Engine Brake
Vehicle Does Not Decelerate by Engine BrakeSYMPTOM:
^ Vehicle does not decelerate by engine brake when shifting from 2[2] (1[2]) to 1[1] "Cruise Test - Part 3".
^ Vehicle does not decelerate by engine brake when OD OFF (OD OFF indicator lamp is on) on "Cruise Test - Part 3".
^ Vehicle does not decelerate by engine brake when shifting A/T from "D" to "2" position on "Cruise Test - Part 3".
DIAGNOSTIC PROCEDURE
1. CHECK CAN COMMUNICATION LINE
Perform self-diagnosis. Refer to AT-73, "CONSULT-III Function (A/T)" or AT-78, "Diagnosis Procedure without CONSULT-III".
Consult-III Function (A/T)
Diagnosis Procedure Without Consult-III
Is a malfunction in CAN communication indicated in the results?
YES >> Check CAN communication line. Refer to AT-83. U1000
NO >> GO TO 2.
2. CHECK OVERDRIVE CONTROL SWITCH CIRCUIT
With CONSULT-III
1. Turn ignition switch ON. (Do not start engine)
2. Select "TCM INPUT SIGNALS" in "DATA MONITOR" mode for "A/T" with CONSULT-III.
3. Read out "OVERDRIVE SW".
Check the signal of the overdrive control switch is indicated properly.
Without CONSULT-III
1. Turn ignition switch ON. (Do not start engine)
2. Check voltage between A/T device harness connector terminal and ground.
OK or NG
OK (With CONSULT-III >> GO TO 3.
OK (Without CONSULT-III >> GO TO 4.
NG >> Check overdrive control switch. Refer to AT-171, "Component Inspection". PNP, OD Switch and Closed Throttle, Wide Open Throttle Position Signal Circuit
3. CHECK PNP SWITCH CIRCUIT
With CONSULT-III
1. Turn ignition switch ON. (Do not start engine.)
2. Select "TCM INPUT SIGNALS" in "DATA MONITOR" mode for "A/T" with CONSULT-III.
3. Readout "P-N", "R", "D", "2" and "1" position switches moving selector lever to each position.
OK or NG
OK >> GO TO 5.
NG >> Check PNP switch. Refer to AT-171, "Component Inspection". PNP, OD Switch and Closed Throttle, Wide Open Throttle Position Signal Circuit
4. CHECK PNP SWITCH CIRCUIT
Without CONSULT-III
1. Turn ignition switch ON. (Do not start engine.)
2. Check voltage between TCM connector terminals and ground while moving selector lever through each position.
OK or NG
OK >> GO TO 5.
NG >> Check PNP switch. Refer to AT-171, "Component Inspection". PNP, OD Switch and Closed Throttle, Wide Open Throttle Position Signal Circuit
5. CHECK A/T POSITION
Check A/T position. Refer to AT-207, "Checking of A/T Position". Procedures
OK or NG
OK >> GO TO 6.
NG >> Adjust A/T position. Refer to AT-207, "Adjustment of A/T Position". Adjustments
6. CHECK VEHICLE SPEED SENSOR-A/T AND VEHICLE SPEED SENSOR-MTR CIRCUIT
Check vehicle speed sensor-A/T (revolution sensor) and vehicle speed sensor-MTR circuit. Refer to AT-96 and/or AT-149.
P0720
DTC Vehicle Speed Sensor MTR
OK or NG
OK >> GO TO 7.
NG >> Repair or replace vehicle speed sensor-A/T (revolution sensor) and/or vehicle speed sensor-MTR circuits.
7. CHECK ACCELERATOR PEDAL POSITION SENSOR
Check accelerator pedal position sensor. Refer to EC-493. P2138
OK or NG
OK >> GO TO 8.
NG >> Repair or replace accelerator pedal position sensor.
8. CHECK A/T FLUID CONDITION
1. Remove oil pan.
2. Check A/T fluid condition. Refer to AT-48, "Inspections Before Trouble Diagnosis". Inspections Before Trouble Diagnosis
OK or NG
OK >> GO TO 10.
NG >> GO TO 9.
9. DETECT MALFUNCTIONING ITEM
1. Remove control valve assembly.
2. Check the following.
- Shift valve A
- Overrun clutch solenoid valve
3. Disassemble A/T.
4. Check the following.
- Overrun clutch assembly.
- Low & reverse brake assembly.
OK or NG
OK >> GO TO 10.
NG >> Repair or replace damaged parts.
10. CHECK SYMPTOM
Check again. Refer to AT-59, "Cruise Test - Part 3". Road Test
OK or NG
OK >> INSPECTION END
NG >> GO TO 11.
11. CHECK TCM
1. Check TCM input/output signals. Refer to AT-71, "TCM Terminal and Reference Value". RE4F03B 4 Speed Automatic Transmission
2. If NG, recheck TCM pin terminals for damage or loose connection with harness connector.
OK or NG
OK >> INSPECTION END
NG >> Repair or replace damaged parts.