Pinpoint Test AD - DTC: U0253:00
Normal Operation and Fault Conditions
The RCM uses information contained in messages from the APIM sent on the HS-CAN.
DTC Fault Trigger Conditions
| DTC | Description | Fault Trigger Conditions |
|---|---|---|
| U0253:00 | Lost Communication with Accessory Protocol Interface Module: No Sub Type Information | This DTC sets if the RCM does not receive an expected message from the APIM for 6 seconds. |
Possible Causes
- Network traffic
- APIM
- RCM
PINPOINT TEST A : U0253:00
- NOTE: Most faults are due to connector and/or wiring concerns. Carry out a thorough inspection and verification before proceeding with the pinpoint test.
- NOTE: Only disconnect or reconnect SRS components when instructed to do so within a pinpoint test step. Failure to follow this instruction may result in incorrect diagnosis of the SRS.
- NOTE: Always make sure the correct SRS component is being installed. Parts released for other vehicles may not be compatible even if they appear physically similar. Check the part number listed in the Ford parts catalog to make sure the correct component is being installed. If an incorrect SRS component is installed, Diagnostic Trouble Codes (DTCs) may set.
- NOTE: The SRS must be fully operational and free of faults before releasing the vehicle to the customer.
- A1 CHECK THE COMMUNICATION NETWORK
- Ignition ON.
- Using a diagnostic scan tool, carry out a network test.
Does the APIM pass the network test?
Yes GO to A2 No To diagnose no communication with the APIM, REFER to: Communications Network . - A2 CHECK THE RCM (RESTRAINTS CONTROL MODULE) CONTINUOUS MEMORY DIAGNOSTIC TROUBLE CODES (CMDTCS)
- Using a diagnostic scan tool, perform RCM self-test.
- Using a diagnostic scan tool, clear RCM Diagnostic Trouble Codes (DTCs).
- Wait 10 seconds.
- Using a diagnostic scan tool, perform RCM self-test.
Is DTC U0253:00 retrieved again?
Yes GO to A3 No The system is operating correctly at this time. The DTC may have been set due to high network traffic or an intermittent fault condition. - A3 RETRIEVE THE RECORDED DIAGNOSTIC TROUBLE CODES (DTCS) FROM THE RCM (RESTRAINTS CONTROL MODULE) SELF-TEST
- Check for recorded Diagnostic Trouble Codes (DTCs) from the RCM self-test.
Is DTC U3003:16 or U3003:17 recorded?
Yes REFER to: Pinpoint Test - DTC: AF . No GO to A4 - A4 RETRIEVE THE RECORDED DIAGNOSTIC TROUBLE CODES (DTCS) FROM THE APIM (SYNC MODULE) SELF-TEST
- Using a diagnostic scan tool, perform APIM self-test.
- Check for recorded Diagnostic Trouble Codes (DTCs) from the APIM self-test.
Is DTC U3003:16 or U3003:17 recorded?
Yes DIAGNOSE the battery voltage Diagnostic Trouble Codes (DTCs). Refer to the appropriate Information and Entertainment Systems article for the procedure. No GO to A5 - A5 CHECK FOR DTC (DIAGNOSTIC TROUBLE CODE) U0253:00 SET IN OTHER MODULES
- Using a diagnostic scan tool, perform self-test for all modules.
Is DTC U0253:00 set in the ACM?
Yes CHECK OASIS for any applicable Technical Service Bulletins (TSBs). If a TSB exists for this concern, DISCONTINUE this test and FOLLOW TSB instructions. If no Technical Service Bulletins (TSBs) address this concern, INSTALL a new APIM. Refer to the appropriate Information and Entertainment Systems article for the procedure. No CHECK OASIS for any applicable Technical Service Bulletins (TSBs). If a TSB exists for this concern, DISCONTINUE this test and FOLLOW TSB instructions. If no Technical Service Bulletins (TSBs) address this concern, INSTALL a new RCM. Refer to: Restraints Control Module (RCM) .