Suzuki XL7 2007 Service Manual page 196

1A-91 Engine General Information and Diagnosis:
Conditions for Setting the DTCs
• A primary HO2S voltage is between 400-600 mV.
• The calculated internal resistance of a primary HO2S
is greater than 20,000 ohms when the calculated
exhaust temperature is greater than 600°C (1112°F).
• A corresponding primary and secondary HO2S are
greater than 200 mV during a decel fuel cut-off.
• DTC P0134 or P0154 set if any of the conditions
above exist for greater than 4 seconds or for a
cumulative of 50 seconds.
Action Taken when the DTC Sets
DTCs P0134 and P0154 are Type B DTCs.
Conditions for Clearing the MIL/DTC
DTCs P0134 and P0154 are Type B DTCs.
Reference Information
Schematic Reference
"Engine Controls Schematics"
Connector End View Reference
• "Engine Control Module Connector End Views"
• "Engine Controls Connector End Views"
Electrical Information Reference
• "Circuit Testing: "
• "Connector Repairs: "
• "Testing for Intermittent Conditions and Poor
Connections: "
• "Wiring Repairs: "
DTC Type Reference
"Powertrain Diagnostic Trouble Code (DTC) Type
Definitions"
Scan Tool Reference
• "Scan Tool Data List - Engine Controls - 3.6L (LY7)"
• "Scan Tool Data Definitions - Engine Controls - 3.6L
(LY7)"
• "Scan Tool Output Controls - Engine Controls - 3.6L
(LY7)"
Circuit/System Verification
1. Engine idling, observe the HO2S voltage parameter.
The voltage should fluctuate above and below the
range of 350-550 mV.
2. If the vehicle passes the Circuit/System Verification
test, then operate the vehicle within the conditions
for running the DTC. You may also operate the
vehicle within the conditions that are captured in the
Freeze Frame/Failure Records Data List.
Circuit/System Testing
1. Ignition OFF, disconnect the harness connector at
the appropriate HO2S.
2. Ignition ON, test for B+ on the HO2S ignition voltage
circuit terminal C of the HO2S harness connector.
➢ If less than the specified value, repair the ignition
voltage circuit for an open/high resistance.
3. Ignition OFF, connect a test lamp between the heater
control circuit terminal D and B+.
4. Idle the engine, and verify the test lamp illuminates
or flashes with bright intensity.
➢ If the test lamp is always OFF, test the control
circuit for an open/high resistance. If the circuit/
connections test normal, replace the ECM.
5. Ignition ON, verify that the applicable HO2S voltage
parameter is between 350-500 mV.
➢ If less than the specified value, test the signal
circuit for a short to ground. If the circuit/
connections test normal, replace the ECM.
➢ If greater than the specified value, test the signal
circuit for a short to voltage. If the circuit/
connections test normal, replace the ECM.
6. Install a 3A fused jumper wire between the signal
circuit terminal B and ground. Verify the HO2S
voltage parameter is less than 60 mV.
➢ If greater than the specified value, test the signal
circuit for an open/high resistance. If the circuit/
connections test normal, replace the ECM.
7. Connect a 3A fused jumper wire between the signal
circuit terminal B and the low reference circuit
terminal A. Verify the HO2S voltage parameter is
less than 60 mV.
➢ If greater than the specified value, test the low
reference circuit for an open/high resistance or for a
short to voltage. If the circuit/connections test
normal, replace the ECM.