Suzuki XL7 2007 Service Manual page 247

Circuit/System Testing
1. Ignition OFF, disconnect the powertrain relay.
NOTE
The test lamp is used to load the circuit and
may not illuminate.
2. Connect a test lamp between the B+ supply circuit to
the coil side of the powertrain relay and the negative
terminal of the battery.
3. Ignition ON, test for less than 0.1 volt between the
B+ voltage circuit of the powertrain relay and the
positive battery terminal.
➢ If greater than 0.1 volt, repair the B+ voltage circuit
to the coil side of the powertrain relay for a short to
ground or an open/high resistance.
NOTE
The test lamp is used to load the circuit and
may not illuminate.
4. Connect a test lamp between the B+ voltage supply
circuit to the switch side of the powertrain relay and
the negative terminal of the battery.
5. Ignition ON, test for less than 0.1 volt between the
B+ voltage circuit of the powertrain relay and the
positive battery terminal.
➢ If greater than 0.1 volt, repair the B+ voltage circuit
to the switch side of the powertrain relay for a short
to ground or an open/high resistance.
6. With the ignition OFF, connect a test lamp between
the control circuit of the powertrain relay and the B+
voltage supply circuit to the coil side of the
powertrain relay.
7. Turn ON the ignition. The test lamp should turn ON
when the ignition switch is cycled ON and OFF when
the ignition switch is cycled OFF.
➢ If the test lamp remains ON all the time, test for a
short to ground on the control circuit. If the circuit/
connections test normal, replace the ECM.
➢ If the test lamp remains OFF all the time, test for a
short to voltage or an open/high resistance on the
control circuit. If circuit/connections test normal,
replace the ECM.
NOTE
The ignition voltage circuit is between the
powertrain relay and the ECM. The ignition
voltage is a feedback circuit.
Engine General Information and Diagnosis:
8. Connect a 15A fused jumper wire between the B+
supply voltage circuit and the ignition voltage circuit
of the powertrain relay.
9. Attempt to start the engine. The engine should start.
➢ If the engine does not start, test the ignition voltage
circuit between the powertrain relay and the ECM
for a short to ground or for an open/high resistance.
If the circuit/connections test normal, replace the
ECM.
10. Ignition ON, test for less than 1 volt on the ignition
voltage circuit between the powertrain relay terminal
in the UBEC and ground.
➢ If greater than the specified value, repair the short
to voltage in the ignition voltage circuit.
11. If all circuits/connections test normal, test or replace
the powertrain relay.
Component Testing
1. Measure for 70-110 ohms of resistance between
terminals 85 and 86 of the powertrain relay.
➢ If the resistance is not within the specified range,
replace the powertrain relay.
2. Measure for infinite resistance between the following
terminals of the powertrain relay:
– 30 and 86
– 30 and 87
– 30 and 85
– 85 and 87
➢ If continuity is detected, replace the powertrain
relay.
3. Connect a 15A fused jumper wire from the positive
terminal of the battery to relay terminal 85. Connect
a jumper wire from the negative terminal of the
battery to relay terminal 86. Measure for less than 2
ohms between terminals 30 and 87 of the relay.
➢ If the resistance measures more than 2 ohms,
replace the powertrain relay.
Repair Instructions
Perform the "Diagnostic Repair Verification - Vehicle
Diagnostic Information: " after completing the diagnostic
procedure.
• "Relay Replacement (Within an Electrical Center): "
"Relay Replacement (Attached to Wire Harness): "
• "Control Module References: " for engine control
module replacement, setup, and programming
1A-142