Hummer H1 (2006+). Instruction - page 68
OBD-116
On-Board Diagnostics
_____________________________________________
6
1.
Connect a 3-amp fused jumper between the signal circuit 324
(YL) of the fuel temperature sensor and the low reference
circuit 252 (BR).
2.
Observe the fuel temperature sensor with the scan tool.
Is the fuel temperature sensor parameter more than the specified
value?
138°C
(280°F)
Go to Step 10
Go to Step 7
7
1.
Turn OFF the ignition.
2.
Connect a 3-amp fused jumper between the signal circuit 324
(YL) of the fuel temperature sensor and a good ground.
3.
Turn ON the ignition, with the engine OFF.
4.
Observe the fuel temperature sensor parameter with a scan
tool.
Is the fuel temperature sensor parameter more than the specified
value?
138°C
(280°F)
Go to Step 9
Go to Step 8
8
Test the fuel temperature sensor signal circuit 324 (YL) for an
open or high resistance between C76 pin 27 and pin B of the fuel
temp sensor.
Did you find and correct the condition?
Go to Step 15
Go to Step 12
9
Test the low reference circuit 252 (BR) of the fuel temperature
sensor for an open or high resistance between C77 pin 48 and pin
A of the fuel temp sensor.
Did you find and correct the condition?
Go to Step 15
Go to Step 12
10
Test the signal circuit 324 (YL) of the fuel temperature sensor for
a short to any other 5-volt reference circuit.
Did you find and correct the condition?
Go to Step 15
Go to Step 11
11
Test for an intermittent and for a poor connection at the fuel tem-
perature sensor.
Did you find and correct the condition?
Go to Step 15
Go to Step 13
12
Test for an intermittent and for a poor connection at the engine
control module (ECM).
Did you find and correct the condition?
Go to Step 15
Go to Step 14
13
Replace the faulty fuel temperature sensor.
Did you complete the replacement?
Go to Step 15
14
Replace the faulty ECM.
Did you complete the replacement?
Go to Step 15
15
1.
Clear the DTCs with a scan tool.
2.
Turn OFF the ignition for 30 seconds.
3.
Start the engine.
4.
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.
Did the DTC fail this ignition?
Go to Step 2
Go to Step 16
16
1.
Using the Scan Tool select “Capture Info,” Review Info.” Are
any DTC’s displayed that have not been diagnosed?
Go to the appli-
cable DTC
table.
System OK.
Step
Action
Value(s)
Yes
No
_____________________________________________
On-Board Diagnostics OBD-117
5745804
DTC P0192 Fuel Rail Pressure Sensor Circuit Low Voltage (Figure OBD-35)
Figure OBD-35: Fuel Rail Pressure Sensor Circuit
Circuit Description
The engine control module (ECM) monitors the fuel rail pressure (FRP) via a FRP sensor. When the fuel rail pressure is high the
signal voltage is high. When the FRP is low the signal voltage is low. If the FRP is not above the lower limit for the sensor, DTC
P0192 will set.
Conditions for Setting the DTC
The ECM detects the signal circuit is less than 1.2 MPa for more than 1 second.
Action Taken When the DTC Sets
• The control module illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails.
• The control module records the operating conditions at the time the diagnostic fails. The control module stores this informa-
tion in the Freeze Frame/Failure Records.
Conditions for Clearing the MIL/DTC
• The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic
runs and does not fail.
• A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
• A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related
diagnostic.
• Clear the MIL and the DTC with a scan tool.
OBD-118
On-Board Diagnostics
_____________________________________________
Step
Action
Value(s)
Yes
No
1
NOTE: Before clearing DTC(s) use the scan tool “Capture info”
to record Freeze Frame and Failure Records for reference, as data
will be lost when “Clear Info” function is used
Was the “On-Board Diagnostic (OBD) System Check” per-
formed?
Go to step 2.
Go to OBD Sys-
tem Check.
2
1.
Install a scan tool.
2.
Turn ON the ignition, with the engine OFF.
3.
Observe the Actual Fuel Rail Pressure parameter with a scan
tool.
Is the Actual Fuel Rail Pressure parameter within the specified
range?
1.2-1.9
MPa
Intermittent Go
To Diagnostic
Aids
Go to Step 3
3
1.
Turn OFF the ignition.
2.
Disconnect the fuel rail pressure (FRP) sensor.
3.
Turn ON the ignition, with the engine OFF.
4.
Observe the Actual Fuel Rail Pressure parameter with a scan
tool.
Is the Actual Fuel Rail Pressure parameter less than the specified
value?
175 MPa
Go to Step 4
Go to Step 5
4
Test the signal circuit 509 (YL) of the FRP sensor for a short to
ground or high resistance between C76 pin 42 and pin A of the
FRP sensor.
Did you find and correct the condition?
Go to Step 7
Go to Step 6
5
Replace the faulty FRP sensor.
Did you complete the replacement?
Go to Step 7
6
Replace the faulty engine control module (ECM).
Did you complete the replacement?
Go to Step 7
7
1.
Clear the DTCs with a scan tool.
2.
Turn OFF the ignition for 30 seconds.
3.
Start the engine.
4.
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.
Did the DTC fail this ignition?
Go to Step 2
Go to Step 8
8
1.
Using the Scan Tool select “Capture Info,” Review Info.” Are
any DTC’s displayed that have not been diagnosed?
Go to the appli-
cable DTC
table.
System OK.
_____________________________________________
On-Board Diagnostics OBD-119
5745804
DTC P0193 Fuel Rail Pressure Sensor Circuit Low Voltage (Figure OBD-36)
Figure OBD-36: Fuel Rail Pressure Sensor Circuit
Circuit Description
The engine control module (ECM) monitors the fuel rail pressure (FRP) via a FRP sensor. When the FRP is high, the signal voltage
is high. When the FRP is low, the signal voltage is low. If the fuel rail pressure is above the upper limit for the sensor, DTC P0193
will set.
Conditions for Setting the DTC
The ECM detects the signal circuit is more than 175 MPa.
Action Taken When the DTC Sets
• The control module illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails.
• The control module records the operating conditions at the time the diagnostic fails. The control module stores this informa-
tion in the Freeze Frame/Failure Records.
• The control module limits fuel injection and FRP.
Conditions for Clearing the MIL/DTC
• The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic
runs and does not fail.
• A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
• A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related
diagnostic.
• Clear the MIL and the DTC with a scan tool.