Chrysler Voyager. Manual — part 210

TEST

ACTION

APPLICABILITY

2

Turn the ignition off.
Reconnect all previously disconnected components.
Connect the DRBIII

t X10 Scope Probe CH7061 to Channel 1 on the DRBIIIt.

Select the following from the DRBIII

t menu: PEP Module Tools; Lab Scope; Live

Data; and Lab Scope.
Press F2 and then press Enter.
Using the left/right arrow keys, set the time to 10ms/Div.
Press F2.
Using the up/down arrow keys, set the voltage range to +20.0v.
Press Enter to move the cursor to Probe.
Using the up/down arrow keys, set the Probe to X10.
Press F2.
Start the engine.
Press the ATC Power switch on.
Using the X10 Scope Probe, back probe the Blower Motor Control circuit in the Front
Blower Power Module C1 harness connector.
NOTE: The Blower Power Module provides a 10.0 volt signal to the ATC
Module over the Blower Motor Control circuit. The ATC Module provides a
variable duty cycle ground to the 10.0 volt signal based on input from the
blower control switch.
NOTE: When the blower control switch is set to LO speed, the ATC Module
provides a short duty cycle (less time grounding the signal voltage).
NOTE: As higher blower speeds are requested, the ATC Module increases
the duty cycle (more time grounding the signal voltage).
NOTE: When the blower control switch reaches HI speed, the duty cycle
increases to where the signal pattern is almost a flat line (with brief voltage
spikes).
Set the blower switch to LO speed then slowly move it to HI speed while observing
the DRBIII

t display.

The voltage on the scope patten should cycle from approximately 2.0 volts (duty cycle
on) to 10.0 volts (duty cycle off) for all blower speeds.
The duty cycle pattern should change smoothly as the blower switch is turned from
LO to HI.
The duty cycle on time should change from approximately 8 ms at LO speed, to 15 ms
at medium speed, and to 25 ms at HI speed.
Does the DRBIII

t display the voltage range and duty cycle as described above?

All

Yes

→ Replace the Front Blower Power Module in accordance with the

Service Information.
With the DRBIII

t, reset the ATC after repair is complete.

Perform BODY VERIFICATION TEST - VER 1.

No

→ Replace the Automatic Temperature Control Module in accor-

dance with the Service Information.
With the DRBIII

t, reset the ATC after repair is complete.

Perform BODY VERIFICATION TEST - VER 1.

267

AUTOMATIC TEMPERATURE CONTROL

*FRONT BLOWER RUNS AT ONLY ONE SPEED —

Continued

Symptom:

*HVAC SYSTEM TEST

POSSIBLE CAUSES

ATTEMPT TO COMMUNICATE WITH THE PCM/ECM, THE BCM, AND THE FCM

CHECK FOR HVAC RELATED DTCS IN THE PCM/ECM

CHECK FOR BCM DTCS

CHECK FOR FCM DTCS

CHECK FOR ACTIVE ATC DTCS

CHECK FOR AC COOLDOWN TEST FAULT MESSAGES

CHECK FOR HVAC RELATED DTCS IN THE PCM/ECM

MANUAL A/C SYSTEM TEST

TEST

ACTION

APPLICABILITY

1

Turn the ignition on.
With the DRBIII

t, attempt to communicate with the Powertrain/Engine Control

Module.
With the DRBIII

t, attempt to communicate with the Body Control Module.

With the DRBIII

t, attempt to communicate with the Front Control Module.

Was the DRBIII

t able to communicate with the PCM/ECM, the BCM, and the FCM?

All

Yes

→ Go To 2

No

→ Refer to the communication category for the related symptom(s).

Perform BODY VERIFICATION TEST - VER 1.

2

With the DRBIII

t, read Powertrain/Engine Computer DTC’s.

Are any HVAC related DTCs present?

All

Yes

→ Refer to the Powertrain Diagnostic Procedures Manual for the

related symptom(s).
Perform BODY VERIFICATION TEST - VER 1.

No

→ Go To 3

3

With the DRBIII

t, read Body Computer DTC’s.

Are any DTCs present?

All

Yes

→ Refer to the appropriate catagory for the related symptom(s).

Perform BODY VERIFICATION TEST - VER 1.

No

→ Go To 4

4

With the DRBIII

t, read Front Control Module DTC’s.

Are any DTCs present?

All

Yes

→ For FCM DTCs related to the blower relay circuits, refer to the

Heating & A/C catagory. For all other FCM DTCs, refer to the
symptom list in the related catagory.
Perform BODY VERIFICATION TEST - VER 1.

No

→ Go To 5

268

AUTOMATIC TEMPERATURE CONTROL

TEST

ACTION

APPLICABILITY

5

NOTE: Active codes must be resolved before diagnosing stored codes.
NOTE: Anytime a code becomes active proceed to the conclusion question.
NOTE: If multiple codes appear, diagnose those that relate to a short circuit
first.
Start the engine.
Press the ATC Power switch on.
Turn the front blower control to the low speed position.
If equipped, turn the rear blower control to the Rear Control position.
Set the Driver, Pass, and, if equipped, Rear temperature controls to 60°F (16°C).
Monitor the DRBIII

t for active ATC DTCs while performing the following test steps.

Press the recirculation mode switch on, wait 30 seconds, and then press it off.
Press the A/C mode switch on, wait 30 seconds, and then press it off.
Press the rear defogger switch on, wait 30 seconds, and then press it off.
Set the Driver temperature control to the max heat setting, wait 30 seconds, and then
set it to the max cool setting. Repeat this step for the Pass and, if equipped, Rear
temperature controls.
Turn the mode control to each position for 30 seconds and then turn it back to the
panel position.
Press the Auto HI switch, wait 30 seconds, and then press the Auto LO switch. When
function is complete, turn the front blower control to the low speed position.
If equipped, on the Rear ATC Control, set the rear temperature control to the max
heat setting, wait 30 seconds, and then set it to the max cool setting.
If equipped, on the Rear ATC Control, turn the mode control to each position for 30
seconds.
With the DRBIII

t in ATC, Miscellaneous, reset the ATC.

Does the DRBIII

t display any active ATC DTCs?

All

Yes

→ Return to the symptom list and choose the symptom(s)

Perform BODY VERIFICATION TEST - VER 1.

No

→ Go To 6

269

AUTOMATIC TEMPERATURE CONTROL

*HVAC SYSTEM TEST —

Continued

TEST

ACTION

APPLICABILITY

6

WARNING: DO NOT OPERATE THE DCHA IN AN ENCLOSED AREA SUCH
AS A GARAGE THAT DOES NOT HAVE EXHAUST VENTILATION FACILI-
TIES. ALWAYS VENT THE DCHA’s EXHAUST WHEN OPERATING THE
DCHA. FAILURE TO FOLLOW THESE INSTRUCTIONS MAY RESULT IN
PERSONAL INJURY OR DEATH.
NOTE: For RG vehicles equipped with a Diesel Cabin Heater Assist (DCHA),
refer to Venting the DCHA’s Exhaust under Cabin Heater in the General
Information portion of this manual for proper exhaust venting instructions.
NOTE: The AC Cooldown Test is actuated with the DRBIII

t. The test checks

A/C system performance based on evaporator temperature sensor input. It
also forces the ATC to initiate a Cabin Heater Activation request when the
vehicle is equipped with a DCHA.
NOTE: The A/C related portion of this test will not run if ambient temp is
below 12°C (53°F). However, the forced Cabin Heater activation will occur
even if the A/C portion of this test fails to initiate because test criteria was
not met.
NOTE: The A/C related portion of this test will pass if evap temp drops 6.7°C
(20°F) within 2 minutes of starting this test.
NOTE: Only A/C related messages display on the DRBIII

t after running this

test. These messages will clear after paging back out of this test. Therefore,
it is important to note all of the test messages before doing so.
NOTE: Running this test will cause the DELAY & Snowflake on the ATC to
flash for 162 seconds (RG with DCHA only). If the A/C related portion of this
test fails, the DELAY & Snowflake LED will continue to flash until the
vehicle is driven more than 3 miles.
Start the engine.
Press the ATC’s Power switch on.
Turn the Mode control to the panel position.
Verify that the front blower motor and, if equipped, rear blower motor operate
correctly in all speeds from each control. Diagnose and repair all blower related faults
before proceeding with this test.
Turn the Front Blower control to the high speed position.
Set the Driver, Pass, and, if equipped, Rear temperature controls to 72°F (22°C).
CAUTION: Do not activate the A/C Cooldown Test with the engine off.
Failure to follow these manuals may result in internal damage to the
DCHA Heater Module.
NOTE: Do not disconnect the vehicle’s battery or the DCHA’s main power
supply while the DCHA is in operation or in run-down mode. Failure to
follow these instructions may result in excess emissions from the DCHA
during heater operation.
NOTE: Before actuating the AC Cooldown Test, verify that the A/C compres-
sor is not running, If the compressor is running, turn the A/C off and allow
the evaporator to warm up before proceeding with the test.
NOTE: The DCHA, if equipped, will operate for approximately 7 minutes. 3
minutes to run and 4 minutes to purge.
With the DRBIII

t in ATC, Systems Tests, perform the AC Cooldown Test.

Does the DRBIII

t display any Cooldown Test fault messages?

All

Yes

→ Return to the symptom list and choose the symptom(s)

Perform BODY VERIFICATION TEST - VER 1.

No

→ Go To 7

270

AUTOMATIC TEMPERATURE CONTROL

*HVAC SYSTEM TEST —

Continued