1999 PCED On Board Diagnostics II |
SECTION 5: Pinpoint Tests |
DR1 DTC P0340: CHECK IF ENGINE WILL START
Will the engine start?
|
Yes
|
No
|
|
GO to DR2
.
|
DTC P0340 is not the cause of the No Start. GO to Section 3
to diagnose
the No Start symptom.
|
DR2 CLEAR AND ATTEMPT TO RE-GENERATE DTC P0340
- Complete PCM Reset to clear DTCs.
- Increase rpm to greater than 1500 rpm for 10 seconds. Repeat two times.
- Retrieve all Continuous Memory DTCs.
Is DTC P0340 present?
|
Yes
|
No
|
For VR type CMP:
KEY OFF. GO to DR5
For Hall Effect type CMP:
KEY OFF. GO to DR3
|
The fault that produced DTC P0340 is intermittent. GO to Pinpoint Test
Step Z1
.
|
DR3 CHECK VPWR VOLTAGE TO CMP SENSOR
- Disconnect CMP sensor.
- Key on, engine off.
- Measure VPWR circuit voltage at the CMP sensor harness connector.
Is voltage greater than 10.5 volts?
|
Yes
|
No
|
|
KEY OFF. GO to DR4
.
|
REPAIR open circuit.
|
DR4 CHECK PWR GND TO CMP SENSOR
- Measure resistance of PWR GND circuit between CMP sensor harness
connector and battery negative post.
Is resistance less than 5.0 ohms?
|
Yes
|
No
|
|
GO to DR5
.
|
REPAIR open circuit.
|
DR5 CHECK FOR OPEN CMP AND SIG RTN CIRCUITS BETWEEN PCM AND CMP SENSOR
Are resistance measurements less than 5.0 ohms?
|
Yes
|
No
|
|
GO to DR6
.
|
REPAIR open circuit.
|
DR6 CHECK CMP CIRCUIT FOR SHORT TO POWER IN HARNESS
- Key on, engine off.
- Measure voltage between CMP and PWR GND circuits at the PCM harness
connector.
Is voltage less than 1.0 volt?
|
Yes
|
No
|
|
KEY OFF. GO to DR7
.
|
REPAIR short circuit.
|
DR7 CHECK CMP CIRCUIT FOR SHORT TO GND AND SIG RTN IN HARNESS
- Disconnect scan tool from DLC.
- Measure resistance between CMP and SIG RTN, and CMP and PWR GND
circuits at the PCM harness connector.
Is each resistance greater than 10,000 ohms?
|
Yes
|
No
|
|
GO to DR8
.
|
REPAIR short circuit.
|
DR8 CHECK FOR SHORTS IN PCM
- Reconnect PCM.
- Measure resistance between CMP and GND, and CMP and VPWR circuits at
the CMP harness connector.
Is each resistance greater than 500 ohms?
|
Yes
|
No
|
For VR type CMP:
GO to DR9
.
For Hall Effect type CMP:
GO to DR10
.
|
REPLACE PCM (refer to Section 2
, Flash EEPROM).
|
DR9 CHECK CMP SENSOR OUTPUT
- Reconnect CMP sensor.
- Digital multimeter on ac scale (to monitor less than 5.0 volts).
- Measure voltage between CMP and PWR GND circuits while running engine
at varying rpm.
Does ac voltage vary greater than 0.1 volt ac?
|
Yes
|
No
|
|
REPLACE PCM (refer to Section 2
, Flash EEPROM).
|
REPLACE CMP sensor.
|
DR10 CHECK CMP SENSOR OUTPUT DURING CRANK MODE
- Disconnect PCM.
- Reconnect CMP sensor.
- Connect digital multimeter between CMP and the CMP sensor GND circuit.
- Bump engine in short bursts with the starter without starting engine
for at least 10 engine revolutions.
Does voltage reading switch between low (less than 2.0 volts dc) and
high (greater than 8.0 volts dc)?
|
Yes
|
No
|
|
A Hall effect type CMP sensor that is installed out of synchronization
will produce a DTC. VERIFY the correct installation by referring to the
Powertrain/Engine Group in the Workshop Manual (Electronic Engine Controls,
Section 303-14). If CMP is installed properly, REPLACE PCM (refer to Section 2
, Flash EEPROM).
|
REPLACE CMP sensor.
|
DR: Introduction