22

No engine braking

DESCRIPTION

• Engine speed drops to idle but the vehicle coasts when the accelerator pedal is released during cruising at medium to high speeds.

• Engine speed drops to idle but the vehicle coasts when the accelerator pedal is released when in M position (1GR) at low vehicle speed.

POSSIBLE CAUSE

• Clutch slippage, burnt (C4 clutch/B1 brake/B2 brake/B4 brake)

• Line pressure low

• VSS malfunction

• Improper signal from PCM (engine speed, accelerator pedal position, engine coolant temperature, engine torque signals)

• Line pressure control solenoid malfunction

• Control valve body malfunction

STEP

INSPECTION

ACTION

1

• Do the following symptoms occur concurrently?

• Engine flares up or slips during acceleration

• Engine flares up or slips when shifting

Yes

Perform the symptom troubleshooting “NO.14 ENGINE FLARES UP OR SLIPS WHEN UPSHIFTING OR DOWNSHIFTING”, or “NO.15 ENGINE FLARES UP OR SLIPS WHEN ACCELERATING VEHICLE”.

(See NO.14 ENGINE FLARES UP OR SLIPS WHEN UPSHIFTING OR DOWNSHIFTING [SJ6A-EL].)

(See NO.15 ENGINE FLARES UP OR SLIPS WHEN ACCELERATING VEHICLE [SJ6A-EL].)

No

Go to the next step.

2

• Access the following PCM PIDs using the M-MDS:

  (See ON-BOARD DIAGNOSTIC TEST [PCM (SKYACTIV-G 2.0)].)

• RPM

• APP

• TP_REL

• ECT

• Are the PIDs value normal?

  (See PCM INSPECTION [SKYACTIV-G 2.0].)

Yes

Go to the next step.

No

Repair or replace the malfunctioning part according to the inspection results.

3

• Stop the engine.

• Inspect the line pressure control solenoid.

  (See SOLENOID VALVE INSPECTION [SJ6A-EL].)

• Is it normal?

Yes

Inspect the ATF condition.

• If a large amount of metal specks are found, overhaul the transmission and repair or replace any malfunctioning parts.

  (See AUTOMATIC TRANSMISSION REMOVAL/INSTALLATION [SJ6A-EL].)

  (See Automatic Transmission Workshop Manual [SJ6A-EL].)

• If a large amount of metal specks are not found, replace the control valve body.

  (See CONTROL VALVE BODY REMOVAL [SJ6A-EL].)

  (See CONTROL VALVE BODY INSTALLATION [SJ6A-EL].)

No

Replace the control valve body.

(See CONTROL VALVE BODY REMOVAL [SJ6A-EL].)

(See CONTROL VALVE BODY INSTALLATION [SJ6A-EL].)

4

• Verify test results.

• If normal, return to the diagnostic index to service any additional symptoms.

• If malfunction remains, inspect the related Service Bulletins and/or On-line Repair Information and perform repair or diagnosis.

• If the vehicle is repaired, troubleshooting completed.

• If the vehicle is not repaired or additional diagnostic information is not available, replace the TCM. (See TCM REMOVAL/INSTALLATION [SJ6A-EL].)