6E–227 ENGINE DRIVEABILITY AND EMISSIONS
DTC P0404 – EGR Open Stuck
StepActionVa l u e ( s )Ye sNo
1Was the “On-Board Diagnostic (OBD) System Check”
performed?
—Go to Step 2
Go to OBD
System
Check
21. Ignition “ON,” engine “OFF”, review and record
Tech 2 Failure Records Data.
2. Operate the vehicle within Failure Records
conditions as noted.
3. Using Tech 2, monitor “Specific DTC” info for DTC
P0404 until the DTC P0404 test runs. Note the
result.
Does Tech 2 indicates DTC P0404 failed this ignition?
—Go to Step 3
Refer to
Diagnostic
Aids
31. Disconnect the EGR valve harness connector.
2. Inspect the EGR valve and connectors for damaged
pin or terminals.
Were there any damaged pins or terminals?
—Go to Step 4Go to Step 5
4Repair the damaged pin or terminal.
—Verify repair
Is the action
complete?
51. Remove EGR valve from Engine.
2. Inspect EGR valve whether there is any excessive
carbon deposit on EGR shaft.
Was excessive carbon deposit 0n EGR valve shaft?
—Go to Step 6Go to Step 7
61. Clean up EGR valve shaft and inside of EGR valve.
2. Visually inspect damage of pintle and seat whether
there is bent, leakage may occur.
Was there any severe damage which affects function?
—Go to Step 8
Verify repair
Go to
Step 7
71. Reconnect.
2. Ignition “OFF”.
3. Install Tech 2.
4. Run the engine at idle.
5. On Tech 2, select F3:Misc. Test; F2:EGR.
6. Use the “UP” arrow to increase the EGR from 0% to
40%.
Did EGR work properly?
——Go to Step 8
8Replace the EGR valve.
Does DTC P0404 still fail “DTC” test on Tech 2?
—Go to Step 9Verify repair
9Replace the PCM.
IMPORTANT:The replacement PCM must be
programmed. Refer to
UBS 98model year Immobilizer
Workshop Manual.
Is the action complete?—Verify repair—
6E–239 ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P0563 System Voltage High
Circuit Description
The powertrain control module (PCM) monitors the
system voltage on the ignition feed terminals to the PCM.
A system voltage DTC will set whenever the voltage is
above a calibrated value.
Conditions for Setting the DTC
Ignition “ON.”
System voltage is above 16 volts for 15 minutes.
Action Taken When the DTC Sets
The PCM will not illuminate the malfunction indicator
lamp (MIL).
The PCM will store as Failure Records only conditions
which were present when the DTC was set. This
information will not be stored as Freeze Frame data.
Conditions for Clearing the MIL/DTC
A history DTC P0563 will clear after 40 consecutive
warm-up cycles have occurred without a fault.
DTC P0563 can be cleared by using the Tech 2 “Clear
Info” function or by disconnecting the PCM battery
feed.
Diagnostic Aids
If the DTC sets when an accessory is operated, check for
a poor connection or excessive current draw.
DTC P0563 – System Voltage High
StepActionVa l u e ( s )Ye sNo
1Was the “ON-Board Diagnostic (OBD) System Check”
performed?
—Go to Step 2
Go to OBD
System
Check
2Using a Tech 2, measure the battery voltage at the
battery.
Is the battery voltage less than the specified value?
11 . 5 VGo to Step 3Go to Step 4
31. Charge the battery and clean the battery terminals.
2. Clean the battery ground cable connection if
corrosion is indicated.
Is the battery voltage less than the specified value?
11 . 5 V
Replace
battery
Go to Step 4
41. Turn “OFF” all the accessories.
2. Install a Tech 2.
3. Select the ignition voltage parameter on the Tech 2.
4. Start the engine and raise the engine RPM to the
specified value.
Is the voltage more than 2.5 volts greater than the
measurement taken in step 2 or 3?
2000 RPM
Go to
Starting/Char
ging
Go to Step 5
5Replace the PCM.
IMPORTANT:The replacement PCM must be
programmed. Refer to
UBS 98 model year Immobilizer
Workshop Manual.
Is the action complete?—Verify repair—
6E–240
ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P0601 PCM Memory
Circuit Description
The powertrain control module (PCM) used in this vehicle
utilizes an electrically erasable programmable read-only
memory (EEPROM). The EEPROM contains program
information and the calibrations required for engine,
transmission, and powertrain diagnostics operation.
Unlike the PROM used in past applications, the EEPROM
is not replaceable.
Conditions for Setting the DTC
The PCM detects an internal program fault (check sum
error).
Action Taken When the DTC Sets
The PCM will not illuminate the malfunction indicator
lamp (MIL).
The PCM will store conditions which were present
when the DTC was set in the Failure Records data only.
Conditions for Clearing the MIL/DTC
DTC P0601 can be cleared by using the Tech 2 “Clear
Info” function or by disconnecting the PCM battery
feed.
Diagnostic Aids
DTC P0601 indicates that the contents of the
EEPROM have changed since the PCM was
programmed. The only possible repair is PCM
replacement.
DTC P0601 – PCM Memory
StepActionVa l u e ( s )Ye sNo
1Was the “On-Board Diagnostic (OBD) System Check”
performed?
—Go to Step 2
Go to OBD
System
Check
2Replace the PCM.
IMPORTANT:The replacement PCM must be
programmed. Refer to
UBS 98model year Immobilizer
Workshop Manual.
Is the action complete?—Verify repair—
6E–245 ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P1171 Fuel System Lean During Acceleration
060RW193–1
Circuit Description
The powertrain control module (PCM) internal circuitry
can identify if the vehicle fuel system is capable of
supplying adequate amounts of fuel during heavy
acceleration (power enrichment). The PCM monitors the
voltage of the oxygen sensor during power enrichment.
When a power enrichment mode of operation is
requested during “closed loop” operation (by heavy
acceleration), the PCM will provide more fuel to the
engine. Under these conditions the PCM should detect a
“rich” condition (high oxygen sensor voltage). If this “rich”
exhaust is not detected at this time, a DTC P1171 will set.
A plugged fuel filter, restricted fuel line, restricted in-tank
filter or defective fuel pump can prevent adequate
amounts of fuel from being supplied during power
enrichment mode.
Conditions for Setting the DTC
No related DTCs.
Engine is operating in “closed loop power enrichment”
mode for 3 seconds.
Engine coolant temperature is above 60C (140F).
While in “power enrichment” mode the oxygen sensor
voltage remains below 400 mV for 3 seconds.
Action Taken When the DTC Sets
The PCM will illuminate the malfunction indicator lamp
(MIL) the first the fault is detected.
The PCM will store conditions which were present
when the DTC was set as Freeze Frame and in the
Failure Records data.
Conditions for Clearing the MIL/DTC
DTC P1171 can be cleared by using Tech 2 “Clear Info”
function or by disconnecting the PCM battery feed.
Diagnostic Aids
A restricted fuel filter or fuel line, restricted in-tank filter,
or a defective fuel pomp may supply adequate
6E–248
ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P1380 ABS Rough Road ABS System Fault
Circuit Description
The powertrain control module (PCM) monitors ABS fault
signal. When PCM receives fault signal, PCM will set
DTC P1380.
Conditions for Setting the DTC
Vehicle speed is more than 5 mph.
Load is less than 99%.
Engine revolution is less than 6250 rpm.
PCM receives ABS fault signals from ABS unit.
Ignition on.
Misfire DTCs exist.
100 test failures within 120 test samples.
Action Taken When the DTC Sets
The PCM will store DTC 1380 only, no MIL turn on.
Conditions for Clearing the MIL/DTC
A history DTC P1380 will clear after 40 consecutive
warm-up cycles have occurred without a fault.
DTC 1380 can be cleared by using Tech-2 or
disconnecting the PCM battery feed.
Diagnostic Aids
Check for the following conditions:
PCM and ABS communication line short circuit to other
line may cause faulty signal. Inspect communication
line.
Follow ABS ECU diagnosis procedure, refer to ABS
procedure page.
DTC P1380 – ABS Rough Road ABS System Fault
StepActionVa l u e ( s )Ye sNo
1Was the “On-Board Diagnostic (OBD) System Check”
performed?
—Go to Step 2
Go to OBD
System
Check
21. Ignition “ON,” engine “OFF”, review and record
Tech 2 Failure Records Data.
2. Operate the vehicle within Failure Records
conditions as noted.
3. Using a Tech 2, monitor “Specific DTC” info for DTC
P1380 and Misfire DTCs until the DTC P1380 and
Misfire DTCs test runs. Note the result.
Does the Tech 2 indicates DTC P1380 and Misfire
DTCs failed this ignition?
—
Refer to ABS
diagnosis
After inspect
ABS, unit re-
peat
Step 2
Still problem
exists, go to
Step 3
Clear DTC by
Te c h 2
3Check short circuit among communication line of
PCM/ABS and others.
Was short circuit?
—
Repair wiring
Verify repair
Go to Step 4
4Replace the PCM.
IMPORTANT:The replacement PCM must be
programmed. Refer to
UBS 98model year Immobilizer
Workshop Manual.
Is the action complete?—Verify repair—
6E–250
ENGINE DRIVEABILITY AND EMISSIONS
DTC P1404 – EGR Closed Stuck
StepActionVa l u e ( s )Ye sNo
1Was the “On-Board Diagnostic (OBD) System Check”
performed?
—Go to Step 2
Go to OBD
System
Check
21. Ignition “ON,” engine “OFF”, review and record
Tech 2 Failure Records Data.
2. Operate the vehicle within Failure Records
conditions as noted.
3. Using a Tech 2, monitor “DTC inf. for DTC P1404
until the DTC P1404 test runs. Note the result.
Does the Tech 2 indicates DTC P1404 failed this
ignition?
—Go to Step 3
Refer to
Diagnostic
Aids
31. Disconnect the EGR valve harness connector.
2. Inspect the EGR valve and connectors for damaged
pin or terminals.
Were there any damaged pins or terminals?
—Go to Step 4Go to Step 5
4Repair the damaged pin or terminal.
Is the action complete?
—Verify repair—
51. Remove EGR valve from Engine.
2. Inspect EGR valve whether there is any excessive
carbon deposit on EGR shaft.
3. Inspect any foreign material inside of EGR valve.
Was excessive carbon deposit on EGR valve shaft
or/and foreign material in EGR valve ?
—Go to Step 6Go to Step 7
61. Clean up EGR valve shaft and inside of EGR valve.
2. Remove foreign material from EGR valve.
3. Visually inspect damage of pintle and seat whether
there is bent, leakage may occur.
Was there any severe damage which affects function?
3–6 ohmsGo to Step 8
Verify repair
Go to
Step 7
71. Reconnect.
2. Ignition “OFF”.
3. Install the Tech 2.
4. Run the engine at idle.
5. On the Tech 2, select F3:Misc. Test F5:EGR.
6. Use the “UP” arrow to increase the EGR from 0% to
40%.
Did EGR work properly?
——Go to Step 8
81. Reset the learned zero EGR valve position.
2. Repeat step 7.
Did EGR work properly?
—Verify repairGo to Step 9
9Replace the EGR valve.
Replace the EGR valve. Does DTC P1404 still fail
“specific DTC” test on the Tech 2?
—Go to Step 10Verify repair
10Replace the PCM.
IMPORTANT:The replacement PCM must be
programmed. Refer to
UBS 98model year Immobilizer
Workshop Manual.
Is the action complete?—Verify repair—
6E–257 ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P1618 Serial Peripheral Interface (SPI) PCM
Interprocessor Communication Error
Circuit Description
The serial peripheral interface (SPI) communication is
used internally by the PCM to send messages between
the engine processor and the automatic transmission
processor. Included in each message sent between the
two-processors is a checksum of the message. Both the
engine processor and automatic transmission processor
will compare this check sum value with the calculated
value. If the checksums don’t match, the processor will
view the new data as being corrupted and ignore the
values. The processor will then use the previous
message. The receiving processor will then send a
message to the sending processor informing it that it’s
last message was corrupted.
Conditions for Setting the DTC
Battery voltage is above 9.0 V for 2 seconds.
The PCM detects an internal program fault (check sum
of data communications error).
Check sum fault present for 3 out 6 seconds.
No TCM resets for 2 seconds.
Action Taken When the DTC Sets
The PCM will flash the “Check Trans” lamp the first
time the fault is detected.
The PCM will store conditions which were present
when the DTC was set as Freeze Frame and in the
Failure Records data.
The automatic transmission will operate in the “safety
mode” to protect the mechanical parts of the
transmission. Shift quality and/or gear changes may
not be normal.
Conditions for Clearing the MIL/DTC
DTC P1618 can be cleared by using the Tech 2 “Clear
Info” function or by disconnecting the PCM battery
feed.
DTC P1618 – Serial Peripheral Interface (SPI) PCM Interprocessor
Communication Error
StepActionVa l u e ( s )Ye sNo
1Was the “On-Board Diagnostic (OBD) System Check”
performed?
—Go to Step 2
Go to OBD
System
Check
2Is the EEPROM calibration the latest version
available?
—Go to Step 4Go to Step 3
3Reprogram the PCM with the latest available
calibrations.
Does DTC 1618 re-appear when the
OBD System
Check
is repeated?—Go to Step 4
Repair
completed
4Replace the PCM.
IMPORTANT:The replacement PCM must be
programmed. Refer to
UBS 98model year Immobilizer
Workshop Manual.
Is the action complete?—Verify repair—
6E–259 ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P1640 Driver-1-Input High Voltage
Circuit Description
Output driver modules (ODMs) are used by the
powertrain control module (PCM) to turn “ON” many of
the current-driven devices that are needed to control
various engine and transmission functions. Each ODM is
capable of controlling up to 7 separate outputs by
applying ground to the device which the PCM is
commanding “ON.”
Unlike the Quad Driver Modules (QDMs) used in prior
model years, ODMs have the capability of diagnosing
each output circuit individually. DTC P1640 set indicates
an improper voltage level has been detected on an ODM
output.
Since A/C is an option, No A/C will cause the air
conditioning clutch relay output to always fault. If a fault is
seen on the air conditioning clutch relay output, it will not
be logged as a fault until the A/C request input interrupts a
high voltage, indicating that A/C has been installed.
Conditions for Setting the DTC
Ignition “ON.”
Engine running.
No DTC 1618.
Ignition voltage is above 13.2 volts for 4 seconds.
Output voltage does not equal ignition voltage when
output is “OFF” or output voltage is not less than 1 volt
when output is “ON.”
Above conditions occur for at least 1 second.
Action Taken When the DTC Sets
The PCM will not illuminate the malfunction indicator
lamp (MIL).
The PCM will store conditions which were present
when the DTC was set as Failure Records only. This
information will not be stored as Freeze Frame data.
Conditions for Clearing the MIL/DTC
DTC P1640 can be cleared by using the Tech 2 “Clear
Info” function or by disconnecting the PCM battery
feed.
Diagnostic Aids
Check for the following conditions:
Poor connection at PCM – Inspect harness connectors
for backed-out terminals, improper mating, broken
locks, improperly formed or damaged terminals, and
poor terminal-to-wire connection.
Damaged harness – Inspect the wiring harness for
damage, If the harness appears to be OK, disconnect
the PCM, turn the ignition “ON” and observe a
voltmeter connected to the suspect driver circuit at the
PCM harness connector while moving connectors and
wiring harnesses relates to the MIL. A change in
voltage will indicate the location of the fault.
Poor connection at component – Examine for
damaged connectors, unplugged connector, or
damaged terminals at the following locations:
Instrument cluster harness, canister purge solenoid,
A/C clutch relay. An open ignition feed circuit at any of
these components will cause DTC P1640 to be set.
Reviewing the Failure Records vehicle mileage since the
diagnostic test last failed may help determine how often
the condition that caused the DTC to be set occurs. This
may assist in diagnosing the condition.
The following PCM pins are controlled by output driver
modules (ODMs):
A13 – “Check Engine Lamp”
A14 – SVS (”Check Trans”)
B14 – A/C Clutch
Test Description
Number(s) below refer to the step number(s) on the
Diagnostic Chart.
6. The Tech 2 Driver Module Status indicates the PCM
pin that is affected.
11. The Tech 2 may indicate “short circuit” even when
the problem is an open circuit. The cause of an
open circuit may be in the component itself-lamp,
purge, solenoid, or A/C compressor relay.
13.A short to ground on the ignition side of the
component will blow the fuse. Since the fuse was
checked in Step 4, a short to ground would be
between the affected component and the PCM.