Pinpoint Test Bk: U0253
WARNING: This page is about a different car, the 2021 Ford F-150. However, it is still accessible from the selected car via links, so may be relevant.
- Normal Operation and Fault Conditions
REFER to: Electric Powertrain Control - Component Location .
DTC Fault Trigger Conditions
DTC Description Fault Trigger Condition SOBDMC U0253:87 Lost Communication With Accessory Protocol Interface Module: Missing Message This DTC sets when messages are missing from the APIM. Possible Sources
- Communications network concern
- APIM
- BK1 CHECK THE COMMUNICATION NETWORK
- Ignition ON.
- Using a diagnostic scan tool, perform a network test.
Does the APIM pass the network test?
Yes GO to BK2 No DIAGNOSE the network concern. - BK2 RETRIEVE THE APIM (SYNC MODULE) DIAGNOSTIC TROUBLE CODES (DTCS)
- Using a diagnostic scan tool, perform the APIM self-test.
Are any APIMDTCs recorded?
Yes REFER to: Information and Entertainment System . No GO to BK3 - BK3 CHECK THE INVERTER SYSTEM CONTROLLER (ISC) DIAGNOSTIC TROUBLE CODES (DTCS)
- Using the scan tool, clear the Inverter System Controller (ISC) DTCs.
- Wait 10 seconds.
- Using a diagnostic scan tool, retrieve the Inverter System Controller (ISC) DTCs.
Is DTC U0253:87 still present?
Yes GO to BK4 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. - BK4 CHECK FOR DTC (DIAGNOSTIC TROUBLE CODE) U0253:87 SET IN OTHER MODULES
- Using the scan tool, clear the Inverter System Controller (ISC) DTCs.
- Ignition OFF.
- Ignition ON.
- Wait 10 seconds.
- Using a diagnostic scan tool, retrieve the Inverter System Controller (ISC) DTCs.
Is DTC U0253:87 set in other modules?
Yes GO to BK5 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. - BK5 CHECK FOR CORRECT APIM (SYNC MODULE) OPERATION
- Ignition OFF.
- Disconnect and inspect all APIM connectors.
- Repair:
- corrosion (install new connector or terminals - clean module pins)
- damaged or bent pins - install new terminals/pins
- pushed-out pins - install new pins as necessary
- Reconnect the APIM connectors. Make sure they seat and latch correctly.
- Ignition ON.
- Operate the system and determine if the concern is still present.
Is the concern still present?
Yes DIAGNOSE the network concern. 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.