Page 225 of 5267

3.(K447) ETC POSITIVE CIRCUIT SHORTED TO BATTERY VOLTAGE
Turn the ignition off.
Disconnect the Throttle Body harness connector.
Disconnect the C2 PCM harness connector.
Ignition on, engine not running.
CAUTION: Do not probe the PCM harness connectors. Probing the
PCM harness connectors will damage the PCM terminals resulting
in poor terminal to pin connection. Install Miller Special Tool #8815
to perform diagnosis.
With a 12-volt test light connected to ground, probe the (K447) ETC
Positive circuit at the appropriate terminal of special tool #8815.
Does the test light illuminate brightly?
Ye s>>
Repair the short to battery voltage on the (K447) ETC Pos-
itive circuit.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to
9 - ENGINE - STANDARD PROCEDURE)
No>>
Go To 4
4.(K448) ETC NEGATIVE CIRCUIT SHORTED TO BATTERY VOLTAGE
Using a 12-volt test light connected to ground, probe the (K448) ETC
Negative circuit at the appropriate terminal of special tool #8815.
Does the test light illuminate brightly?
Ye s>>
Repair the short to battery voltage in the (K448) ETC Neg-
ative circuit.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to
9 - ENGINE - STANDARD PROCEDURE)
No>>
Go To 5
5.(K447) ETC POSITIVE CIRCUIT SHORTED TO THE (K448) ETC NEGATIVE CIRCUIT
Measure the resistance between the (K447) ETC Positive circuit and
the (K448) ETC Negative circuit at the appropriate terminals of special
tool #8815.
Istheresistancebelow100ohms?
Ye s>>
Repair the short to between the (K447) ETC Positive circuit
and the (K448) ETC Negative circuit.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to
9 - ENGINE - STANDARD PROCEDURE)
No>>
Go To 6
Page 226 of 5267
6.(K447) ETC POSITIVE CIRCUIT OPEN
Turn the ignition off.
Measure the resistance of the (K447) ETC Positive circuit from the
Throttle Body harness connector to the appropriate terminal of special
tool #8815.
Is the resistance below 5.0 ohms?
Ye s>>
Go To 7
No>>
Repair the open in the (K447) ETC Positive circuit.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to
9 - ENGINE - STANDARD PROCEDURE)
7.(K447) ETC POSITIVE CIRCUIT SHORTED TO GROUND
Measure the resistance between ground and the (K447) ETC Positive
circuit between the appropriate terminals of special tool #8815.
Istheresistancebelow100ohms?
Ye s>>
Repair the short to ground in the (K447) ETC Positive cir-
cuit.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to
9 - ENGINE - STANDARD PROCEDURE)
No>>
Go To 8
Page 227 of 5267
8.(K448) ETC NEGATIVE CIRCUIT OPEN
Measure the resistance of the (K448) ETC Negative circuit from the
Throttle Body harness connector to the appropriate terminal of special
tool #8815.
Is the resistance below 5.0 ohms?
Ye s>>
Go To 9
No>>
Repair the open in the (K448) ETC Negative circuit.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to
9 - ENGINE - STANDARD PROCEDURE)
9.(K448) ETC NEGATIVE CIRCUIT SHORTED TO GROUND
Measure the resistance between ground and the (K448) ETC Negative
circuit between the appropriate terminals of special tool #8815.
Istheresistancebelow100ohms?
Ye s>>
Repair the short to ground in the (K448) ETC Negative cir-
cuit.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to
9 - ENGINE - STANDARD PROCEDURE)
No>>
Go To 10
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10.ETC MOTOR
NOTE: Take the following measurement using special tool #8815 to
avoid possible damage to the Throttle Body harness connector.
Measure the resistance of the ETC Motor between the (K447) ETC
Positive circuit and the (K448) ETC Negative circuit at the appropriate
terminals of special tool #8815.
Is the resistance between 2.5 and 25 ohms at closed throttle?
Ye s>>
Go To 11
No>>
Replace the Throttle Body Assembly. Disconnect the Battery
when replacing the Throttle Body Assembly. After installa-
tion is complete, use a scan tool and select the ETC
RELEARN function.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to
9 - ENGINE - STANDARD PROCEDURE)
11 .PCM
NOTE: Before continuing, check the PCM harness connector terminals for corrosion, damage, or terminal
push out. Repair as necessary.
Using the schematics as a guide, inspect the wire harness and connectors. Pay particular attention to all Power and
Ground circuits.
Were there any problems found?
Ye s>>
Repair as necessary.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
No>>
Replace and program the Powertrain Control Module per Service Information.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
Page 229 of 5267
P2122-ACCELERATOR PEDAL POSITION SENSOR 1 CIRCUIT LOW
For a complete wiring diagramRefer to Section 8W.
Page 230 of 5267

When Monitored:
With the ignition on and no other APPS No.1 DTCs present.
Set Condition:
When the APP Sensor No.1 voltage is toolow. Engine will additionally idle if the brake pedal is pressed or has
failed. Acceleration rate and Engine output are limited. One trip fault and the code will set within 5 seconds.
ETC light is flashing.
Possible Causes
(F855) 5-VOLT SUPPLY CIRCUIT OPEN
(F855) 5-VOLT SUPPLY CIRCUIT SHORTED TO GROUND
(K23) APP SENSOR NO.1 SIGNAL CIRCUIT OPEN
(K23) APP SENSOR NO.1 SIGNAL CIRCUIT SHORTED TO GROUND
(K23) APP SENSOR NO.1 SIGNAL CIRCUIT SHORTED TO THE (K167) APP SENSOR NO.1 RETURN CIRCUIT
(K23) APP SENSOR NO.1 SIGNAL CIRCUIT SHORTED TO THE (K400) APP SENSOR NO.2 RETURN CIRCUIT
APP SENSOR
PCM
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 9 - ENGINE -
DIAGNOSIS AND TESTING).
Diagnostic Test
1.APP SENSOR BELOW 0.25 OF A VOLT
Ignition on, engine not running.
With a scan tool, read the APP Sensor No.1 voltage.
Is the voltage below 0.25 of a volt?
Ye s>>
Go To 2
No>>
Go To 11
2.(F855) 5-VOLT SUPPLY CIRCUIT
Turn the ignition off.
Disconnect the APP Sensor harness connector.
Ignition on, engine not running.
Measure the voltage on the (F855) 5-volt Supply circuit in the APP Sen-
sor harness connector.
Is the voltage between 4.5 and 5.2 volts?
Ye s>>
Go To 3
No>>
Go To 8
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3.ACCELERATOR PEDAL POSITION SENSOR
Connect a jumper wire between the (F855) 5-volt Supply circuit and the
(K23) APP Sensor No.1 Signal circuit in the Sensor harness connector.
With a scan tool, monitor the APP Sensor No.1 voltage.
Is the voltage above 4.5 volts?
Ye s>>
Replace the APP Sensor Assembly per Service Information.
After installation is complete, use a scan tool and select the
ETC RELEARN function to relearn the APPS values.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to
9 - ENGINE - STANDARD PROCEDURE)
No>>
Go To 4
NOTE: Remove the jumper wire before continuing.
4.(K23) APP SENSOR NO.1 SIGNAL CIRCUIT OPEN
Turn the ignition off.
Disconnect the C3 PCM harness connector.
CAUTION: Do not probe the PCM harness connectors. Probing the
PCM harness connectors will damage the PCM terminals resulting
in poor terminal to pin connection. Install Miller Special Tool #8815
to perform diagnosis.
Measure the resistance of the (K23) APP Sensor No.1 Signal circuit
from the APP Sensor harness connector to the appropriate terminal of
special tool #8815.
Is the resistance below 5.0 ohms?
Ye s>>
Go To 5
No>>
Repair the open in the (K23) APP Sensor No.1 Signal cir-
cuit.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to
9 - ENGINE - STANDARD PROCEDURE)
Page 232 of 5267
5.(K23) APP SENSOR NO.1 SIGNAL CIRCUIT SHORTED TO GROUND
Measure the resistance between ground and the (K23) APP Sensor
No.1 Signal circuit in the APP Sensor harness connector.
Istheresistancebelow100ohms?
Ye s>>
Repair the short to ground in the (K23) APP Sensor No.1
Signal circuit.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to
9 - ENGINE - STANDARD PROCEDURE)
No>>
Go To 6
6.(K23) APP SENSOR NO.1 SIGNAL CIRCUIT SHORTED TO THE (K167) APP SENSOR NO.1 RETURN
CIRCUIT
Measure the resistance between the (K23) APP Sensor No.1 Signal cir-
cuit and the (K167) Sensor No.1 Return circuit at the APP Sensor har-
ness connector.
Istheresistancebelow100ohms?
Ye s>>
Repair the short between the (K167) App Sensor No.1
Return circuit and the (K23) APP Sensor No.1 Signal circuit.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to
9 - ENGINE - STANDARD PROCEDURE)
No>>
Go To 7