Hummer H1 Service Manual page 1183

118 PCM/Tech 1 Scan Tool
DTC P1654 - Check Throttle Circuit
Step
1 Important: 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" performed?
2 1. Ignition "ON" engine "OFF".
2. Using a scan tool, command the lamp ON and OFF.
Does the Check Throttle lamp turn ON and OFF with each command?
3 DTC is intermittent. If no additional DTCs are stored, refer to "Diagnostic
Aids". If additional DTCs are stored, refer to those charts(s) first.
Are additional DTCs stored?
4 1. Ignition "OFF".
2. Disconnect the blue 32 way PCM electrical connector.
3. Ignition "ON" engine "OFF".
Is the lamp "OFF"?
5 With a fused jumper wire connected to ground, probe the lamp control cir-
cuit in the PCM harness connector.
Is the lamp ON?
6 1. Check for poor connections at PCM.
2. If a problem was found, repair as necessary.
Was a repair performed?
7 Check Throttle control circuit is shorted to ground.
Is the action complete?
8 Check the Check Throttle control circuit for the following:
• opens
• poor connection at PCM
• faulty bulb
• faulty fuse.
Was a problem found?
9 Replace the faulty PCM. Notice: If the PCM is faulty, the new PCM must
be programmed. Go to PCM replacement and programming procedures.
Is the action complete?
10 1. Using the Scan Tool, select "DTC", "Clear Info".
2. Start engine and idle at normal operating temperature.
3. Select "DTC", "Specific", then enter the DTC number which was set.
4. Operate vehicle within the conditions for setting this DTC as specified in
the supporting text.
Does the Scan Tool indicate that this diagnostic Ran and Passed?
11 Using the Scan Tool, select "Capture Info", "Review Info".
Are any DTCs displayed that have not been diagnosed?
___________________________________________________
Action Value(s) Yes
— Go to Step 2.
— Go to Step 3.
— Go to
applicable
DTC table.
— Go to Step 5.
— Go to Step 6.
— Go to Step 10.
— Go to Step 10.
— Go to Step 10.
— Go to Step 10.
— Go to Step 11. Go to Step 2.
— Go to the
applicable
DTC table
®
No
Go to OBD
System Check.
Go to Step 4.
Go to
Diagnostic Aids
Go to Step 7.
Go to Step 8.
Go to Step 9.
—
—
—
System OK.