Dodge Viper SRT-10 (ZB). Manual - part 328

Symptom List:

A/C SWITCH FAULT (STORED)
BACKLIGHT DIMMING RX FAILURE (STORED)
BLEND OVERCURRENT (STORED)
CHECKSUM FAILURE (STORED)
DEFOG SWITCH FAULT (STORED)
LOOPBACK TEST FAILURE (STORED)
MODE 1 OVERCURRENT (STORED)
MODE 2 OVERCURRENT (STORED)
RECIRC OVERCURRENT (STORED)
REFRIGERANT PRESS RX FAILURE (STORED)
TX FAILURE (STORED)
VIN RX FAILURE (STORED)

Test Note:

All symptoms listed above are diagnosed using the same tests.

The title for the tests will be A/C SWITCH FAULT (STORED).

When Monitored and Set Condition:

A/C SWITCH FAULT (STORED)

When Monitored:

With the ignition on.

Set Condition:

This DTC will set if the A/C on/off switch stays closed for 10 minutes.

BACKLIGHT DIMMING RX FAILURE (STORED)

When Monitored:

With the ignition on.

Set Condition:

If the A/C - Heater Control Module does not receive the dimming function

message from the Body Control Module for more than 5 seconds, then the A/C - Heater
Control Module backlighting will default to full brightness and the DTC will set.

BLEND OVERCURRENT (STORED)

When Monitored:

When actuator movement is requested.

Set Condition:

This DTC will set if the A/C - Heater Control Module detects an excessive

current draw on any of the door driver circuits while attempting to drive this actuator.
Only one overcurrent DTC can set per ignition cycle.

CHECKSUM FAILURE (STORED)

When Monitored:

At every power up (five seconds after ignition is on).

Set Condition:

This DTC will set if the calculated check sum does not match the stored

value.

DEFOG SWITCH FAULT (STORED)

When Monitored:

With the ignition on.

Set Condition:

This DTC will set if the EBL switch stays closed for 10 minutes.

205

HEATING & A/C

LOOPBACK TEST FAILURE (STORED)

When Monitored:

When the A/C - Heater Control Module executes an internal loopback

test.

Set Condition:

If the A/C - Heater Control Module fails to send a message, or none of the

expected messages arrive for 5 seconds, an internal loopback test is executed. If the
internal loopback test fails, the DTC will set.

MODE 1 OVERCURRENT (STORED)

When Monitored:

When actuator movement is requested.

Set Condition:

This DTC will set if the A/C - Heater Control Module detects an excessive

current draw on any of the door driver circuits while attempting to drive this actuator.
Only one overcurrent DTC can set per ignition cycle.

MODE 2 OVERCURRENT (STORED)

When Monitored:

When actuator movement is requested.

Set Condition:

This DTC will set if the A/C - Heater Control Module detects an excessive

current draw on any of the door driver circuits while attempting to drive this actuator.
Only one overcurrent DTC can set per ignition cycle.

RECIRC OVERCURRENT (STORED)

When Monitored:

When actuator movement is requested.

Set Condition:

This DTC will set if the A/C - Heater Control Module detects an excessive

current draw on any of the door driver circuits while attempting to drive this actuator.
Only one overcurrent DTC can set per ignition cycle.

REFRIGERANT PRESS RX FAILURE (STORED)

When Monitored:

With the ignition on.

Set Condition:

This DTC will set if the A/C - Heater Control Module does not receive the

Refrigerant Pressure message from the PCM for more than 20 seconds.

TX FAILURE (STORED)

When Monitored:

When the ignition is on.

Set Condition:

This DTC will set if the A/C - Heater Control Module is unable to send a

PCI Bus message.

VIN RX FAILURE (STORED)

When Monitored:

With the ignition on.

Set Condition:

This DTC will set if the A/C - Heater Control Module does not receive the

VIN message from the PCM for more than 5 seconds.

206

HEATING & A/C

A/C SWITCH FAULT (STORED) —

Continued

POSSIBLE CAUSES

CHECK FOR ACTIVE HVAC DTCS AND SYSTEM TEST FAULT MESSAGES

STORED CODE(S) TEST COMPLETE

TEST

ACTION

APPLICABILITY

NOTE: Active DTCs must be resolved before diagnosing stored DTCs.
NOTE: Anytime a DTC becomes active, or an Actuator Circuit Test fault
message is displayed, or a Door Recalibration fault message is displayed,
proceed to the conclusion question.
Turn the ignition on.
Turn the mode select control to the panel position.
Verify that the blower motor operates correctly in all speeds. Diagnose and repair all
blower related faults before proceeding with this test.
Turn the blower control to the low speed position.
Turn the blend control to the full cold position.
Monitor the DRBIII

t for active HVAC DTCs during the following test steps.

Press the A/C switch on, wait 30 seconds, and then press it off.
Press the EBL switch on, wait 30 seconds, and then press it off.
Slowly turn the blend control from full cold to full hot, wait 30 seconds, and then turn
it back to full cold.
Turn the mode select control to every door position. Leave it in each position for
approximately 30 seconds.
With the DRBIII

t in HVAC, System Tests, actuate the Actuator Circuit Test.

With the DRBIII

t in HVAC, System Tests, actuate the HVAC Door Recalibration

Test.
Does the DRBIII

t display any HVAC DTCs or System Test fault messages?

All

Yes

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

Perform BODY VERIFICATION TEST - VER 1.

→ No problem found at this time.

Perform BODY VERIFICATION TEST - VER 1.

207

HEATING & A/C

A/C SWITCH FAULT (STORED) —

Continued

Symptom List:

ACT CKT TEST PASSED, OVERCURRENT DTCS ACTIVE
BLEND CIRCUIT SHORTED TO GROUND
BLEND CIRCUIT SHORTED TO IGN OR BATT
COMMON DRIVER SHORTED TO GROUND
COMMON DRIVER SHORTED TO IGN OR BATT
MODE 1 CIRCUIT SHORTED TO GROUND
MODE 1 CIRCUIT SHORTED TO IGN OR BATT
MODE 2 CIRCUIT SHORTED TO GROUND
MODE 2 CIRCUIT SHORTED TO IGN OR BATT
RECIRC CIRCUIT SHORTED TO GROUND
RECIRC CIRCUIT SHORTED TO IGN OR BATT
SHORT TOO COMPLEX

Test Note:

All symptoms listed above are diagnosed using the same tests.

The title for the tests will be ACT CKT TEST PASSED, OVER-
CURRENT DTCS ACTIVE.

When Monitored and Set Condition:

ACT CKT TEST PASSED, OVERCURRENT DTCS ACTIVE

When Monitored: