Workshop Manual

6E–74
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
B P1275, P1639, P1271, P1273
B P1285, P1272, P1273
B P0336, P0337
B P1220, P1515, P1221, P1515, P1516
B P1280, P1271, P1272
Check for the following conditions:
B Poor connection at PCM. Inspect the harness
connectors for backed–out terminals, improper
mating, broken locks, improperly formed or damage
terminals, and a poor terminal–to–wire connection.
B Damaged harness. Inspect the wiring harness for
damage. If the harness is not damaged, observe an
affected sensor fs displayed value on the Tech 2 with
the ignition “ON” and the engine “OFF” while you
move the connectors and the wiring harnesses
related to the following sensors:
B Vapor Pressure (Fuel Tank Pressure) Sensor
B MAP Sensor
B EGR
B TPS1/TPS2
B APS1/APS2/APS3
B CKP
Multiple PCM Information Sensor DTCs Set
Step Action Value(s) Yes No
1 Was the “On-Board (OBD) System Check” performed?
— Go to Step 2
Go to OBD
System
Check
2 1. Turn the ignition “OFF”, disconnect the PCM.
2. Turn the ignition “ON”, check the 5 volt reference 1
and 2 circuit for the following conditions:
B A poor connection at the PCM.
B An open between the PCM connector and the
splice.
B A short to ground.
B A short to voltage.
Is there an open or short?
— Go to Step 3 Go to Step 4
3 Repair the open or short.
Is the action complete?
— Verify repair —
4 Check the sensor ground circuit for the following
conditions:
B A poor connection at the PCM or the affected
sensors.
B An open between the PCM connector and the
affected sensors.
Is there an open or a poor connection?
— Go to Step 5 Go to Step 6
5 Repair the open or the poor connection.
Is the action complete?
— Verify repair —
6 Following below the DTCs stored:
P1635, P1639
—
Go to
applicable
DTC table
Go to Step 7
7 Measure the resistance below the items:
B Between EGR sensor supply circuit and Vapor
Pressure Sensor supply circuit.
B Between MAP sensor supply circuit and Vapor
Pressure Sensor supply circuit.
B Between Vapor Pressure Sensor supply circuit
and PCM harness connector. (5Volt supply
circuit)
Is the resistance near the specified value?
— Go to Step 9 Go to Step 8