Pinpoint Test S: U0155:00
WARNING: This page is about a different car, the 2023 Ford Bronco. However, it is still accessible from the selected car via links, so may be relevant.
- Refer to
AUTOMATIC CLIMATE CONTROL SYSTEM
for schematic and connector information.
Normal Operation and Fault Conditions
With the ignition ON, the IPC sends messages to the HVAC control module over the MS-CAN. If the HVAC control module does not receive these messages within the specified time frame, the module sets a DTC. This can be due to an IPC failure, a circuit failure on the MS-CAN or an excessive load on the network. For information on the messages sent to the HVAC control module by the IPC, REFER to: Climate Control System - Vehicles With: Dual Automatic Temperature Control (DATC) - System Operation and Component Description .
DTC Fault Trigger Conditions
DTC Description Fault Trigger Condition HVAC U0155:00 Lost Communication With Instrument Panel Cluster (IPC) Control Module: No Sub Type Information If data messages received from the IPC over the MS-CAN are missing for 5 seconds or more. Possible Sources
- Network communication concern
- Wiring, terminals or connectors
- Over or undervoltage concerns
- IPC
- HVAC control module
- S1 VERIFY THE CUSTOMER CONCERN
- Ignition ON.
- Verify there is an observable symptom present.
Is an observable symptom present?
Yes GO to S2 No CLEAR the DTC. The system is operating normally at this time. The DTC may have been set due to high network traffic or an intermittent fault condition. - S2 CHECK THE COMMUNICATION NETWORK
- Using a diagnostic scan tool, carry out the network test.
Does the IPC pass the network test?
Yes GO to S3 No DIAGNOSE the IPC does not communicate with the diagnostic scan tool, REFER to: Controller Area Network (CAN) Module Communications Network . - S3 RETRIEVE THE RECORDED DIAGNOSTIC TROUBLE CODES (DTCS) FROM THE IPC (INSTRUMENT PANEL CLUSTER) SELF-TEST
- Using a diagnostic scan tool, carry out the IPC self-test.
Are any Diagnostic Trouble Codes (DTCs) recorded?
Yes REFER to: Instrumentation, Message Center and Warning Chimes . No GO to S4 - S4 RETRIEVE THE RECORDED DIAGNOSTIC TROUBLE CODES (DTCS) FROM THE (HVAC) HEATING, VENTILATION AND AIR CONDITIONING CONTROL MODULE SELF-TEST
- Using a diagnostic scan tool, carry out the HVAC control module self-test.
Is DTC U3003:16 or DTC U3003:17 recorded?
Yes For U3003:16 GO to Pinpoint Test AB For U3003:17 GO to Pinpoint Test AC No GO to S5 - S5 RECHECK THE (HVAC) HEATING, VENTILATION AND AIR CONDITIONING CONTROL MODULE DIAGNOSTIC TROUBLE CODES (DTCS)NOTE: If new modules were installed prior to the Diagnostic Trouble Code (DTC) being set, the module configuration can be incorrectly set during the Programmable Module Installation (PMI) or the Programmable Module Installation (PMI) may not have been carried out.
- Using a diagnostic scan tool, clear the Diagnostic Trouble Codes (DTCs).
- Ignition OFF.
- Ignition ON.
- Wait 10 seconds.
- Using a diagnostic scan tool, carry out the HVAC control module self-test.
Is DTC U0155:00 still present?
Yes GO to S6 No CLEAR the DTC. The system is operating correctly at this time. The DTC may have been set due to high network traffic or an intermittent fault condition. - S6 CHECK FOR DTC (DIAGNOSTIC TROUBLE CODE) U0155:00 SET IN OTHER MODULES
- Using a diagnostic scan tool, clear all Diagnostic Trouble Codes (DTCs).
- Ignition OFF.
- Ignition ON.
- Wait 10 seconds.
- Using a diagnostic scan tool, retrieve all continuous memory Diagnostic Trouble Codes (DTCs).
Is DTC U0155:00 set in other modules on the network?
Yes GO to S7 No GO to S8 - S7 CHECK FOR CORRECT IPC (INSTRUMENT PANEL CLUSTER) OPERATION
- Ignition OFF.
- Disconnect and inspect the IPC electrical connector (if not previously disconnected).
- Repair:
- corrosion (install new connector or terminal - clean module pins)
- damaged or bent pins - install new terminals or pins
- pushed-out pins - install new pins as necessary
- Connect IPC electrical connector. Make sure it seats and latches correctly.
- Operate the system and determine if the concern is still present.
Is the concern still present?
Yes CHECK OASIS for any applicable service articles: TSB, GSB, SSM or FSA. If a service article exists for this concern, DISCONTINUE this test and FOLLOW the service article instructions. If no service articles address this concern, INSTALL a new IPC. REFER to: Instrument Panel Cluster (IPC) . No The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. ADDRESS the root cause of any connector or pin issues. - S8 CHECK FOR CORRECT HVAC (HEATING, VENTILATION AND AIR CONDITIONING) CONTROL MODULE OPERATION
- Ignition OFF.
- Disconnect and inspect all HVAC control module electrical connectors (if not previously disconnected).
- Repair:
- corrosion (install new connector or terminal - clean module pins)
- damaged or bent pins - install new terminals or pins
- pushed-out pins - install new pins as necessary
- Connect all HVAC control module electrical connectors. Make sure they seat and latch correctly.
- Operate the system and determine if the concern is still present.
Is the concern still present?
Yes CHECK OASIS for any applicable service articles: TSB, GSB, SSM or FSA. If a service article exists for this concern, DISCONTINUE this test and FOLLOW the service article instructions. If no service articles address this concern, INSTALL a new HVAC control module. REFER to: Heating, Ventilation and Air Conditioning (HVAC) Control Module . No The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. ADDRESS the root cause of any connector or pin issues.