Dodge Ram 2004 Service Manual page 399

COOLDOWN TEST TOO COLD TO START —
TEST
3 CAUTION: The work area ambient temperature must be above 21.1°C (70°F)
to test A/C system operation.
Turn the ignition on.
With the DRBIII , check the PCM for any DTCs.
Are any DTCs present?
Yes → Refer to the Powertrain Diagnostic Information. After the repair
→ Go To 4
No
4 Turn the ignition off.
Disconnect the Evaporator Temperature Sensor harness connector.
Turn the ignition on.
With the DRBIII
voltage.
Is the voltage above 4.9 volts?
Yes → Go To 5
→ Go To 6
No
5 Turn the ignition off.
Disconnect the Evaporator Temperature Sensor harness connector.
Connect a jumper wire between the Evaporator Temperature Sensor Signal circuit
and the Sensor Ground circuit at the Evaporator Temperature Sensor harness
connector.
Turn the ignition on.
With the DRBIII
voltage.
Is the voltage below 0.10 volt?
Yes → Replace the Evaporator Temperature Sensor in accordance with
→ Go To 6
No
6 NOTE: Ensure that the Evaporator Temperature Sensor harness connector
is connected to the Evaporator Temperature Sensor.
NOTE: Ensure that the voltmeter leads meet the terminals in the connector
and that there is good terminal to wire connection.
NOTE: Ensure the voltmeter leads are connected for positive polarity.
Back probe the Sensor Ground circuit between the Evaporator Temperature Sensor
harness connector and the A/C - Heater Control Module C1 harness connector.
Turn the ignition on.
Is the voltage below 0.10 volt?
Yes → Go To 7
→ Repair the high resistance in the Sensor Ground circuit. After the
No
ACTION
is complete, with the DRBIII , erase the DTC(s). Cycle the
ignition switch. Start the engine. Set the blower control to high
speed. With the DRBIII , actuate the Cooldown Test.
Perform BODY VERIFICATION TEST - VER 1.
in Sensor Display, read the Evaporator Temperature Sensor
in Sensor Display, read the Evaporator Temperature Sensor
the Service Information. After the repair is complete, start the
engine. Set the blower control to high speed. With the DRBIII ,
actuate the Cooldown Test.
Perform BODY VERIFICATION TEST - VER 1.
repair is complete, start the engine. Set the blower control to high
speed. With the DRBIII , actuate the Cooldown Test.
Perform BODY VERIFICATION TEST - VER 1.
Continued
385
HEATING & A/C
APPLICABILITY
All
All
All
All