Pinpoint Test H : U0121:00
WARNING: This page is about a different car, the 2018 Lincoln Navigator. However, it is still accessible from the selected car via links, so may be relevant.
- H1 VERIFY THE SCAN TOOL COMMUNICATES WITH THE ABS (ANTI-LOCK BRAKE SYSTEM)
- Ignition ON.
- Connect a diagnostic scan tool.
- Check that a vehicle session can be established using a diagnostic scan tool.
Can a vehicle session be established?
Yes GO to H2 No REFER to: Communications Network . - H2 CHECK THE BCM (BODY CONTROL MODULE) CMDTC (CONTINUOUS MEMORY DIAGNOSTIC TROUBLE CODE) S
- Using a diagnostic scan tool, perform the BCM self-test.
- Clear the DTCs.
- Wait 10 seconds.
- Repeat the BCM self-test.
Is DTC U0121 retrieved again?
Yes GO to H3 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. - H3 RETRIEVE THE RECORDED DTC (DIAGNOSTIC TROUBLE CODE) S FROM THE ABS (ANTI-LOCK BRAKE SYSTEM) MODULE SELF-TEST
- Using a diagnostic scan tool, perform the ABS module self-test.
Are any DTCs recorded?
Yes REFER to: Anti-Lock Brake System (ABS) and Stability Control . No GO to H4 - H4 RETRIEVE THE RECORDED DTC (DIAGNOSTIC TROUBLE CODE) S FROM THE PCM SELF-TEST
- Using a diagnostic scan tool, perform the PCM self-test.
Is DTC P0562:00 or P0563:00 recorded?
Yes DIAGNOSE and REPAIR all charging or battery related DTCs first. REFER to: Charging System . No GO to H5 - H5 CHECK FOR DTC (DIAGNOSTIC TROUBLE CODE) U0121 SET IN OTHER MODULES
- Using a diagnostic scan tool, clear all DTCs.
- Ignition OFF.
- Ignition ON.
- Wait 10 seconds.
- Using a diagnostic scan tool, perform the continuous memory self-test.
- Retrieve the CMDTCs from all modules.
Is DTC U0121 set in other modules on the network?
Yes GO to H6 No GO to H7 - H6 CHECK FOR CORRECT ABS (ANTI-LOCK BRAKE SYSTEM) MODULE OPERATION
- Ignition OFF.
- Disconnect and inspect the ABS module connector.
- Check for the following:
- 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 ABS module connector. Make sure they seat and latch correctly.
- Operate the system and verify the concern is still present.
Is the concern still present?
Yes CHECK OASIS for any applicable TSBs. If a TSB exists for this concern, DISCONTINUE this test and FOLLOW TSB instructions. If no TSBs address this concern, INSTALL a new ABS module. REFER to: Anti-Lock Brake System (ABS) Module . No The system is operating correctly at this time. The concern may have been caused by module connections. ADDRESS the root cause of any connector or pin issues. - H7 CHECK FOR CORRECT BCM (BODY CONTROL MODULE) OPERATION
- Ignition OFF.
- Disconnect and inspect the BCM connector.
- Check for the following:
- 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 BCM connectors. Make sure they seat and latch correctly.
- Operate the system and verify the concern is still present
Is the concern still present?
Yes CHECK OASIS for any applicable TSBs. If a TSB exists for this concern, DISCONTINUE this test and FOLLOW TSB instructions. If no TSBs address this concern, BCM guided routine is not applicable for this vehicle and market. Replace the component that was faulted through service information diagnosis. No The system is operating correctly at this time. The concern may have been caused by module connections. ADDRESS the root cause of any connector or pin issues.