Hummer H1 Service Manual page 270

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Step
3 1. Turn the ignition OFF.
2. Disconnect the OSS Sensor connector from the
OSS Sensor.
3. Connect a J– 39200 DVOM on AC Voltage scale
between terminals A and B at the OSS Sensor.
4. Start the engine, and place the transmission in D3
range.
5. Slowly increase the wheel speed.
Is the voltage greater than the specified value?
4 1. Reconnect the OSS Sensor connector to the OSS
Sensor.
2. Disconnect the VSS Buffer harness from the VSS
Buffer.
3. Measure the voltage between terminals 7 and 12 of
the Buffer Harness Connector. Use the J– 39200
DVOM.
4. Start the engine, and place the transmission in D3.
5. With the wheels turning, slowly accelerate to 2000
RPM.
Is the voltage greater than the specified value?
5
Inspect circuits 821 and 822 for an open. Refer to Elec-
trical Diagnosis, Section 8.
Did you find a problem?
6 Inspect circuits 821 and 822 for a short together or a
short to ground. Refer to Electrical Diagnosis, Section 8.
Did you find a problem?
7 1. Turn the ignition to the OFF position.
2. Measure the voltage between terminal 9 of the VSS
Buffer connector, and a good ground with the J–
39200 DVOM on DC volts.
3. Turn the ignition ON.
Is the voltage greater than the specified valve?
8 Inspect the ignition feed circuit 39 for an open.
Did you find a problem?
9 With the key to the ON position, measure the voltage
between terminals 8 and 9 of the VSS Buffer connector.
Is the voltage greater than the specified valve?
10 Inspect the VSS Buffer Module ground circuit 451 for
an open.
Was the problem found and corrected?
05745159
DTC P0722 Output Speed Sensor Low Input (Cont'd)
Action
Transmission/Transfer Case
Value
Greater than
0.5 volts at
above 10 mph.
Go to Step 4
0.5 volts AC
Go to Step 7
__
Go to Step 16
__
Go to Step 16
10.5 volts DC
Go to Step 9
__
Go to Step 21
10.5 volts DC
Go to Step 11
__
Go to Step 21
5-71
Yes No
Go to Step 18
Go to Step 5
Go to Step 6
__
Go to Step 8
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Go to Step 10
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