Engine Control System (4HK1) 1A-329
Exhaust Brake Control System Check
Description
The exhaust brake control system consists of the ECM,
the intake throttle valve, the exhaust brake valve, the
exhaust brake solenoid valve and the exhaust brake
switch. The ECM commands the intake throttle
solenoid valve and the exhaust brake solenoid valve to
close each valve based on vehicle running conditions
and exhaust brake switch input signal.
Exhaust Brake Control Operation
• The exhaust brake switch is ON.
• The engine is running.
• The accelerator pedal is not depressed.
• The gearshift clutch is not disengaged (Smoother).
• The clutch pedal is not depressed (M/T).
• The vehicle speed is higher than predetermined
range.
Test Description
The number below refers to the step number on the
Circuit/ System Table.
4. Use the scan tool to observe the Accelerator Pedal
Position. The Accelerator Pedal Position parameter
should change linearly from 0 to 100% according to the
accelerator pedal operation.
8. If the Exhaust Brake Solenoid Command parameter
indicates OFF, use the scan tool to observe the Vehicle
Speed, Accelerator Pedal Position and Clutch Switch
parameters which allows the exhaust brake control.
Refer to Engine Controls Schematic and Scan Tool
Data List for diagnosis.
Schematic Reference:
Engine Controls Schematics
Connector End View Reference:
Engine Controls
Connector End Views or ECM Connector End Views
Circuit/ System Testing Exhaust Brake Control System Check (1 of 2)
Step
Action
Value(s)
Yes
No
1
Did you perform the Diagnostic System Check
- Engine Controls?
—
Go to Step 2
Go to Diagnostic
System Check -
Engine Controls
2
1.
Verify whether the instrument panel (IP)
cluster is operational.
2.
Start the engine.
3.
Apply the exhaust brake switch ON and OFF.
Does the exhaust brake indicator lamp turn
ON and OFF with each switch transition?
—
Go to Step 3
Go to 2 of 2 Step 1
3
1.
Drive the vehicle in order to gain exhaust
brake ON time long enough.
2.
Apply the exhaust brake switch ON.
3.
Release the accelerator pedal.
Does exhaust brake apply enough (if the
vehicle speed is reduced by applying the
exhaust brake but engine valve noise is
heard, intake throttle valve may not be closed
enough)?
—
Go to Step 4
Go to Step 7
4
1.
Reenter the exhaust brake control.
2.
Apply the accelerator pedal while in exhaust
brake control.
Does the exhaust brake control cancel?
—
Go to Step 5
Observe the
Accelerator Pedal
Position parameter
for accelerator pedal
position sensor
diagnosis
5
Notice:
If no Smoother is installed, skip to Step 6.
1.
Reenter the exhaust brake control.
2.
Operate the selector lever while in exhaust
brake control.
Does the exhaust brake control cancel?
—
System OK
Go to Diagnostic
System Check -
Transmission
Controls in Section
5A Transmission
Control System
LG4HKED-WE-0871.book 329
ページ
２００７年１１月２９日 木曜日 午後６時２９分
