2001 CHRYSLER VOYAGER sensor

Symptom:
EVAP TEMP SENSOR OPEN
When Monitored and Set Condition:
EVAP TEMP SENSOR OPEN
When Monitored: During the Cooldown Test.
Set Condition: This message is displayed if the ATC detects an abnormally high voltage
on the evaporator temperature sensor signal during the Cooldown Test.
POSSIBLE CAUSES
EVAPORATOR TEMPERATURE SENSOR
EVAPORATOR TEMPERATURE SENSOR SIGNAL CIRCUIT OPEN
SENSOR GROUND CIRCUIT OPEN
AT C
TEST ACTION APPLICABILITY
1 Turn the ignition off.
Disconnect the in-line C202 harness connector.
Connect a jumper wire between the Evaporator Temperature Sensor Signal circuit
and the Sensor Ground circuit at the in-line C202 harness connector (HVAC side).
Turn the ignition on.
With the DRBIIItin Sensor Display, read the Evaporator Temperature Sensor
voltage.
Does the DRBIIItdisplay: 0.0 volts?All
Ye s®Check the wiring harness between the in-line C202 harness
connector (plenum side) and the Evap Temp Sensor for an open.
Repair as necessary. If Ok, replace the Evaporator Temperature
Sensor.
With the DRBIIIt, reset the ATC after repair/replacement is
complete.
Perform BODY VERIFICATION TEST - VER 1.
No®Go To 2
2 Turn the ignition off.
Disconnect the ATC C2 harness connector.
Disconnect the in-line C202 harness connector.
Measure the resistance of the Evaporator Temperature Sensor Signal circuit between
the ATC C2 harness connector and the in-line C202 harness connector.
Is the resistance below 5.0 ohms?All
Ye s®Go To 3
No®Repair the Evaporator Temperature Sensor Signal circuit be-
tween the ATC C2 harness connector and the in-line C202
harness connector (HVAC side) for an open.
With the DRBIIIt, reset the ATC after repair/replacement is
complete.
Perform BODY VERIFICATION TEST - VER 1.
241
AUTOMATIC TEMPERATURE CONTROL

TEST ACTION APPLICABILITY
3 Turn the ignition off.
Disconnect the ATC C2 harness connector.
Disconnect the in-line C202 harness connector.
Measure the resistance of the Sensor Ground circuit between the ATC C1 harness
connector and the in-line C202 harness connector.
Is the resistance below 5.0 ohms?All
Ye s®Replace the ATC.
With the DRBIIIt, reset the ATC after repair/replacement is
complete.
Perform BODY VERIFICATION TEST - VER 1.
No®Repair the Sensor Ground circuit between the ATC C2 harness
connector and the in-line C202 harness connector (HVAC side) for
an open.
With the DRBIIIt, reset the ATC after repair/replacement is
complete.
Perform BODY VERIFICATION TEST - VER 1.
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AUTOMATIC TEMPERATURE CONTROL
EVAP TEMP SENSOR OPEN ÐContinued

Symptom:
EVAP TEMP SENSOR SHORTED
When Monitored and Set Condition:
EVAP TEMP SENSOR SHORTED
When Monitored: During the Cooldown Test.
Set Condition: This message is displayed if the ATC detects an abnormally low voltage on
the evaporator temperature sensor signal during the Cooldown Test.
POSSIBLE CAUSES
EVAPORATOR TEMPERATURE SENSOR
EVAPORATOR TEMPERATURE SENSOR SIGNAL CIRCUIT SHORT TO GROUND
EVAPORATOR TEMPERATURE SENSOR SIGNAL CIRCUIT SHORT TO SENSOR GROUND CIR-
CUIT
AT C
TEST ACTION APPLICABILITY
1 Turn the ignition off.
Disconnect the in-line C202 harness connector.
Turn the ignition on.
With the DRBIIItin Sensor Display, read the Evaporator Temperature Sensor
voltage.
Does the DRBIIItdisplay: 5.0 volts or greater?All
Ye s®Check the Evap Temp Sensor Signal circuit between the in-line
C202 harness connector (plenum side) and the Evap Temp Sensor
for a short to ground. Repair as necessary. If Ok, replace the
Evaporator Temperature Sensor.
With the DRBIIIt, reset the ATC after repair/replacement is
complete.
Perform BODY VERIFICATION TEST - VER 1.
No®Go To 2
2 Turn the ignition off.
Disconnect the ATC C2 harness connector.
Disconnect the in-line C202 harness connector.
Measure the resistance between ground and the Evaporator Temperature Sensor
Signal circuit (HVAC side).
Is the resistance above 100k ohms?All
Ye s®Go To 3
No®Repair the Evaporator Temperature Sensor Signal circuit be-
tween the ATC C2 harness connector and the in-line C202
harness connector (HVAC side) for a short to ground.
With the DRBIIIt, reset the ATC after repair/replacement is
complete.
Perform BODY VERIFICATION TEST - VER 1.
243
AUTOMATIC TEMPERATURE CONTROL

TEST ACTION APPLICABILITY
3 Turn the ignition off.
Disconnect the ATC C2 harness connector.
Disconnect the in-line C202 harness connector.
Measure the resistance between the Evaporator Temperature Sensor Signal circuit
and the Sensor Ground circuit (HVAC side).
Is the resistance above 100k ohms?All
Ye s®Replace the ATC.
With the DRBIIIt, reset the ATC after repair/replacement is
complete.
Perform BODY VERIFICATION TEST - VER 1.
No®Repair the Evaporator Temperature Sensor Signal circuit be-
tween the ATC C2 harness connector and the in-line C202
harness connector (HVAC side) for a short to Sensor Ground.
With the DRBIIIt, reset the ATC after repair/replacement is
complete.
Perform BODY VERIFICATION TEST - VER 1.
244
AUTOMATIC TEMPERATURE CONTROL
EVAP TEMP SENSOR SHORTED ÐContinued

Symptom List:
FRONT IR SENSOR AND CONTROL HEAD MISMATCH (ACTIVE)
FRONT IR SENSOR CHANGE TOO LARGE (ACTIVE)
FRONT IR SENSOR HIGH (ACTIVE)
FRONT IR SENSOR LOW (ACTIVE)
Test Note: All symptoms listed above are diagnosed using the same tests.
The title for the tests will be FRONT IR SENSOR AND
CONTROL HEAD MISMATCH (ACTIVE).
When Monitored and Set Condition:
FRONT IR SENSOR AND CONTROL HEAD MISMATCH (ACTIVE)
When Monitored: Every 8 seconds with the ignition on.
Set Condition: This condition is set if the ATC does not receive the intake air temperature
response message within 8 seconds.
FRONT IR SENSOR HIGH (ACTIVE)
When Monitored: With the ignition on and the IOD fuse installed.
Set Condition: This DTC is set if the ATC reads the Front IR Sensor value and it is above
250 A/D counts.
FRONT IR SENSOR LOW (ACTIVE)
When Monitored: With the ignition on and the IOD fuse installed.
Set Condition: This DTC is set if the ATC reads the Front IR Sensor value and it is below
5 A/D counts.
POSSIBLE CAUSES
ATC REMOTE SENSOR
TEST ACTION APPLICABILITY
1 This DTC indicates a fault in the ATC Remote Sensor.
View repair.All
Repair
Replace the ATC Remote Sensor.
With the DRBIIIt, reset the ATC after repair/replacement is
complete.
Perform BODY VERIFICATION TEST - VER 1.
245
AUTOMATIC TEMPERATURE CONTROL

Symptom List:
FRONT IR SENSOR NOT CALIBRATED (ACTIVE)
FRONT KEYBOARD FAULT (ACTIVE)
Test Note: All symptoms listed above are diagnosed using the same tests.
The title for the tests will be FRONT IR SENSOR NOT
CALIBRATED (ACTIVE).
When Monitored and Set Condition:
FRONT IR SENSOR NOT CALIBRATED (ACTIVE)
When Monitored: With the ignition on and the IOD fuse installed.
Set Condition: This DTC is set if the ATC cannot read the IR sensor values or the IR
sensor values are not within a defined range of the HVAC air door motor counts.
POSSIBLE CAUSES
ATC - PROTECTED IGNITION CIRCUIT FAULT
KDB 2 CLOCK CIRCUIT SHORTED TO VOLTAGE
KDB 2 DATA CIRCUIT SHORTED TO GROUND
KDB 2 DATA CIRCUIT SHORTED TO VOLTAGE
PROTECTED IGNITION CIRCUIT OPEN
SENSOR RETURN CIRCUIT OPEN
KDB 2 CLOCK CIRCUIT SHORTED TO GROUND
KDB 2 DATA CIRCUIT OPEN
ATC - KDB 2 DATA CIRCUIT FAULT
ATC - SENSOR RETURN CIRCUIT FAULT
KDB 2 CLOCK CIRCUIT OPEN
ATC - KDB 2 CLOCK CIRCUIT FAULT
ATC REMOTE SENSOR
TEST ACTION APPLICABILITY
1 Turn the ignition off.
Disconnect the ATC Remote Sensor harness connector.
Turn the ignition on.
Measure the voltage of the Protected Ignition circuit.
Is the voltage above 10.0 volts?All
Ye s®Go To 2
No®Go To 16
246
AUTOMATIC TEMPERATURE CONTROL

TEST ACTION APPLICABILITY
2 Turn the ignition off.
Disconnect the ATC Remote Sensor harness connector.
Turn the ignition on.
Measure the voltage of the KDB 2 Data circuit.
Is the voltage above 10.0 volts?All
Ye s®Go To 3
No®Go To 13
3 Turn the ignition off.
Disconnect the ATC Remote Sensor harness connector.
Disconnect the ATC C3 harness connector.
Turn the ignition on.
Measure the voltage of the KDB 2 Data circuit.
Is the voltage above 1.0 volt?All
Ye s®Repair the KDB 2 Data circuit for a short to voltage.
With the DRBIIIt, reset the ATC after repair/replacement is
complete.
Perform BODY VERIFICATION TEST - VER 1.
No®Go To 4
4 Turn the ignition off.
Disconnect the ATC Remote Sensor harness connector.
Use Scope input cable CH7058, Cable to Probe adapter CH7062, and the red and
black test probes.
Connect the scope input cable to the channel one connector on the DRB. Attach the
red and black leads and the cable to probe adapter to the scope input cable.
Select Lab Scope.
Select Live.
Select 12 volt square wave.
Press F2 for Scope.
Press F2 and use the arrows to set the voltage range to 20 volts, the Offset to 4.0, and
the Probe to x10. Press F2 again and set the divisions to 40ms/Div, then press F2
again when complete.
Connect the Black lead to the chassis ground. Connect the Red lead to the KDB 2
Clock circuit in the ATC Remote Sensor harness connector.
Turn the ignition on.
Observe the voltage display on the DRB Lab Scope.
NOTE: The lab scope pattern should look similar to the example given in the
support material and cycle from approximately 0 volts to 8.0 volts.
Did the lab scope pattern and voltage react as noted above?All
Ye s®Go To 5
No®Go To 9
5 Turn the ignition off.
Disconnect the ATC Remote Sensor harness connector.
Measure the resistance between ground and the Sensor Return circuit.
Is the resistance below 10 ohms?All
Ye s®Go To 6
No®Go To 7
247
AUTOMATIC TEMPERATURE CONTROL
FRONT IR SENSOR NOT CALIBRATED (ACTIVE) ÐContinued

TEST ACTION APPLICABILITY
6 If there are no possible causes remaining, view repair. All
Repair
Replace the ATC Remote Sensor.
With the DRBIIIt, reset the ATC after repair/replacement is
complete.
Perform BODY VERIFICATION TEST - VER 1.
7 Turn the ignition off.
Disconnect the ATC Remote Sensor harness connector.
Measure the resistance of the Sensor Return circuit.
Is the resistance below 5.0 ohms?All
Ye s®Go To 8
No®Repair the Sensor Return circuit for an open.
With the DRBIIIt, reset the ATC after repair/replacement is
complete.
Perform BODY VERIFICATION TEST - VER 1.
8 If there are no possible causes remaining, view repair. All
Repair
Replace the ATC.
With the DRBIIIt, reset the ATC after repair/replacement is
complete.
Perform BODY VERIFICATION TEST - VER 1.
9 Turn the ignition off.
Disconnect the ATC Remote Sensor harness connector.
Disconnect the ATC C3 harness connector.
Turn the ignition on.
Measure the voltage of the KDB 2 Clock circuit.
Is the voltage above 1.0 volt?All
Ye s®Repair the KDB 2 Clock circuit for a short to voltage.
With the DRBIIIt, reset the ATC after repair/replacement is
complete.
Perform BODY VERIFICATION TEST - VER 1.
No®Go To 10
10 Turn the ignition off.
Disconnect the ATC Remote Sensor harness connector.
Disconnect the ATC C3 harness connector.
Measure the resistance between ground and the KDB 2 Clock circuit.
Is the resistance above 100k ohms?All
Ye s®Go To 11
No®Repair the KDB 2 Clock circuit for a short to ground.
With the DRBIIIt, reset the ATC after repair/replacement is
complete.
Perform BODY VERIFICATION TEST - VER 1.
248
AUTOMATIC TEMPERATURE CONTROL
FRONT IR SENSOR NOT CALIBRATED (ACTIVE) ÐContinued