Suzuki XL7 2007 Service Manual page 1552

5A-142 Automatic Transmission:
Circuit/System Testing
1. Engine ON, with the scan tool, observe the TR Sw.
parameter while selecting each transmission range:
P, R, N, D5, D4, D3, D2, and D1. Each selected
transmission range should correspond to the correct
scan tool PNP Switch parameter displayed.
➢ If not equal to the specified range, Test the Starter
Inhibit Circuit for a short to ground, an open/high
resistance, or a short to voltage. If the circuit test
normal, replace the TCM.
DTC P0851 or P0852
Diagnostic Instructions
• Perform the "Diagnostic System Check - Vehicle Diagnostic Information: " prior to using this diagnostic procedure.
• "Strategy Based Diagnosis: "Strategy Based Diagnosis
• "Diagnostic Procedure Instructions - Vehicle Diagnostic Information: "
DTC Descriptor
DTC P0851: Park/Neutral Position (PNP) Switch Circuit Low Voltage
DTC P0852: Park/Neutral Position (PNP) Switch Circuit High Voltage
Diagnostic Fault Information
Circuit
Starter Inhibit (PNP) Circuit
Circuit/System Description
The transmission range (TR) switch is an integral part of
the transmission control module (TCM). As the gear
range selector lever is moved, the state of the Starter
Inhibit Circuit may change, causing the circuit to open or
close. An open circuit indicates a drive range and a low
voltage signal, 0 volts, at the engine control module
(ECM). A closed circuit indicates PARK or NEUTRAL
and a high voltage, 12 volts, signal at the ECM.
The ECM uses the Starter Inhibit circuit status from the
TCM in order to enable starter operation.
Conditions for Running the DTC
• Start Lock Driving voltage is within 6.0-16.0 volts.
• Ignition voltage is greater than 6.5 volts.
Conditions for Setting the DTC
DTC P0851
The ECM detects "ON" signal from the Starter Inhibit
Circuit while the TCM is commanding the Starter Inhibit
Circuit "OFF" for 0.5 second.
DTC P0852
The ECM detects "OFF" signal from the Starter Inhibit
Circuit while the TCM is commanding the Starter Inhibit
Circuit "ON" for 0.5 second.
2. With the scan tool, observe the PNP Switch
parameter (Engine Electrical/Theft Data) while
selecting each transmission range: P, R, N, D5, D4,
D3, D2, and D1. Each selected transmission range
should correspond to the correct scan tool PNP
Switch parameter displayed (Park/Neutral/In Gear).
➢ If not equal to the specified range, test the Starter
Inhibit Circuit for a short to ground, an open/high
resistance, or a short to voltage. If the circuit tests
normal, replace the ECM.
Repair Instructions
Perform the "Diagnostic Repair Verification - Vehicle
Diagnostic Information: " after completing the diagnostic
procedure.
Short to Open/High
Ground Resistance
P0851 P0851
Action Taken When the DTC Sets
None
Conditions for Clearing the DTC
DTC P0851 and P0852 are Type C DTCs.
Reference Information
Schematic Reference
"Automatic Transmission Controls Schematics"
Connector End View Reference
• "Automatic Transmission Internal Connector End
Views"
• "Automatic Transmission Related Connector End
Views"
Scan Tool Reference
• "Scan Tool Output Controls - Automatic Transaxle -
AF33-5"
• "Scan Tool Data List - Automatic Transaxle - AF33-5"
• "Scan Tool Data Definitions - Automatic Transaxle -
AF33-5"
Signal
Short to Voltage
Performance
P0852 —