Suzuki XL7 2007 Service Manual page 188

1A-83 Engine General Information and Diagnosis:
Circuit/System Verification
1. Verify that the engine coolant level is correct.
➢ If the engine coolant is not at the correct level, refer
to "Loss of Coolant: ".
2. Verify that the engine coolant temperature is at the
normal operating temperature.
➢ If the engine coolant temperature is below normal
operating temperature, refer to "Thermostat
Diagnosis: ".
3. Operate the vehicle within the conditions for running
the DTC. You may also operate the vehicle within the
conditions that you observed from the Freeze
Frame/Failure Records. DTC P0125 or P0128
should not set.
4. 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 List.
Circuit/System Testing
1. Ignition OFF, disconnect the harness connector at
the ECT sensor.
CAUTION
!
Do NOT use a test lamp to test the continuity
of the circuit. Damage to the control module
may occur due to excessive current draw.
NOTE
The control module or the sensor may be
damaged if the circuit is shorted to battery
positive voltage.
2. Test for less than 5 ohms of resistance between the
low reference circuit terminal 2 and ground.
➢ If greater than 5 ohms, test the low reference circuit
for a short to voltage or an open/high resistance. If
the circuit tests normal, replace the ECM.
3. Ignition ON, using a scan tool verify that the ECT
sensor parameter is at −40°C (−40°F).
➢ If greater than −40°C (−40°F), test the signal circuit
for a short to ground. If the circuit/connections test
normal, replace the ECM.
NOTE
If the fuse in the jumper wire opens, the
signal circuit is shorted to a voltage and the
ECT sensor may be damaged.
4. Install a 3-amp fused jumper wire between the signal
circuit terminal 1and the low reference circuit
terminal 2. Verify the ECT sensor parameter is
greater than 142°C (288°F).
➢ If less than the specified value, test the signal
circuit for an open/high resistance or for a short to
voltage. If the circuit/connections test normal,
replace the ECM.
5. If all circuits test normal, test or replace the ECT
sensor.
Component Testing
1. Ignition OFF, disconnect the harness connector of
the ECT sensor.
NOTE
A thermometer can be used to the used to
test the sensor off the vehicle.
2. Test the ECT sensor by varying the sensor
temperature while monitoring the sensor resistance.
Compare the readings with the "Temperature Versus
Resistance - Engine Coolant Temperature Sensor"
table and verify that the resistance is within 5 percent
of the specification.
➢ If the resistance vs. temperature is not within 5
percent, replace the ECT sensor.
Repair Instructions
Perform the "Diagnostic Repair Verification - Vehicle
Diagnostic Information: " after completing the diagnostic
procedure.
• "Engine Coolant Temperature Sensor Replacement: "
• "Control Module References: " for engine control
module replacement, setup, and programming