Suzuki XL7 2007 Service Manual page 252

1A-147 Engine General Information and Diagnosis:
Circuit/System Description
Correct engine misfire detection is dependent on
whether or not the vehicle is experiencing a rough road
condition. A rough road condition causes unexpected
crankshaft fluctuations. In order to detect a rough road
condition, the electronic brake control module (EBCM)
communicates a wheel speed signal over the serial data
circuit to the engine control module (ECM). The wheel
speed sensor information allows the ECM to distinguish
if the crankshaft speed variations are caused by a rough
road condition or are caused by a true misfire.
Conditions for Running the DTC
• The engine is operating.
• DTC P1380 runs continuously once the above
conditions are met for more than 5 seconds.
Conditions for Setting the DTC
• The ECM detects an engine misfire while the rough
road signal is unavailable.
• The condition exists for more than 4 seconds or a
cumulative of 50 seconds.
Action Taken When the DTC Sets
DTC P1380 is a Type C DTCs.
Conditions for Clearing the DTC
DTC P1380 is a Type C DTCs.
Reference Information
DTC Type Reference
"Powertrain Diagnostic Trouble Code (DTC) Type
Definitions"
Circuit/System Testing
Start and idle the engine, observe the DTC information
with a scan tool.
NOTE
If any UXXXX DTCs are set, diagnose those
first.
➢ If DTC P1380 failed this ignition, refer to
"Diagnostic Starting Point - Antilock Brake System:
".
Repair Instructions
Perform the "Diagnostic Repair Verification - Vehicle
Diagnostic Information: " after completing the diagnostic
procedure.
"Control Module References: " for engine control module
replacement, setup, and programming
DTC P1551
Diagnostic Instructions
• Perform the "Diagnostic System Check - Vehicle
Diagnostic Information: " prior to using this diagnostic
procedure.
• Review "Strategy Based Diagnosis: " for an overview
of the diagnostic approach.
• "Diagnostic Procedure Instructions - Vehicle
Diagnostic Information: " provides an overview of
each diagnostic category.
DTC Descriptor
DTC P1551: Throttle Valve Rest Position Not Reached
During Learn
Circuit/System Description
The engine control module (ECM) controls the throttle
valve by applying a varying voltage to the control circuits
of the throttle actuator control (TAC) motor. The ECM
monitors the duty cycle that is required to actuate the
throttle valve. The ECM monitors the throttle position
(TP) sensors 1 and 2 to determine the actual throttle
valve position.
Conditions for Running the DTC
• The vehicle speed is 0 km/h (0 mph).
• The engine speed is less than 40 RPM.
• The engine coolant temperature (ECT) is between 5-
100°C (41-212°F).
• The intake air temperature (IAT) is between 5-143°C
(41-290°F).
• The ignition 1 voltage is more than 10 volts.
• The accelerator pedal position (APP) is less than 15
percent.
• DTC P1551 runs when the throttle actuator control
motor is deactivated.
Conditions for Setting the DTC
The ECM detects the TP sensor angle is less than 10
percent or more than 40 percent when the throttle
actuator control motor is deactivated.
Action Taken When the DTC Sets
DTC P1551 is a type A DTC.
Conditions for Clearing the DTC
DTC P1551 is a type A DTC.