DTC U0127 (Gauge Control Module (Without CAN Gateway)) (2016 2017 2018 2019 2020)

DTC U0127  : Gauge control module lost communication with TPMS control unit

DTC (Gauge Control Module)

NOTE: 

• Before you troubleshoot, record all freeze data and any on-board snapshot, and review the general troubleshooting information - Refer to:

  How to Troubleshoot the Fuel and Emissions Systems (2014 2015 2016 2017 2018 2019 2020) or

  How to Troubleshoot the Fuel and Emissions Systems (With Auto Idle Stop System) (2016 2017 2018 2019 2020)

• If you are troubleshooting multiple DTCs, be sure to follow the instructions in B-CAN System Diagnosis Test Mode A - Refer to: Body Electrical Troubleshooting - B-CAN System Diagnosis Test Mode A - Initial Communication and DTC Checks (2014 2015 2016) or Body Electrical Troubleshooting - B-CAN System Diagnosis Test Mode A - Initial Communication and DTC Checks (2017 2018 2019 2020)

1. Problem verification

   - 1. Clear the DTCs with the HDS.

   - 2. Turn the vehicle to the OFF (LOCK) mode and then the ON mode.

   - 3. Wait for at least 6 seconds.

   - 4. Check for DTCs with the HDS.

   DTC Description	DTC
   U0127 Gauge Control Module Lost Communication With Keyless Access/TPMS Control Unit

   Is DTC U0127 indicated?

   YES 

   Go to step 2.

   NO 

   Intermittent failure, the system is OK at this time. Check for loose or poor connections.

2. Fuse check

   - 1. Check the following fuse.

   Fuse	No. D23 (7.5 A)
   Location	Driver's under-dash fuse/relay box

   Is the fuse OK?

   YES 

   Go to step 3.

   NO 

   Replace the fuse. If the fuse blows again, repair a short to ground in the No. D23 (7.5 A) fuse circuit.

3. Open wire check (IG1 SAFETY line)

   - 1. Turn the vehicle to the OFF (LOCK) mode.

   - 2. Disconnect the following connectors.

   Keyless access/TPMS control unit connector A (32P)

   Keyless access/TPMS control unit connector B (36P)

   Keyless access/TPMS control unit connector C (20P)

   - 3. Turn the vehicle to the ON mode.

   - 4. Measure the voltage between test points 1 and 2.

   Test condition	Vehicle ON mode Keyless access/TPMS control unit connector A (32P): disconnected Keyless access/TPMS control unit connector B (36P): disconnected Keyless access/TPMS control unit connector C (20P): disconnected
   Test point 1	Keyless access/TPMS control unit connector B (36P) No. 34 - Refer to: Keyless Access System (Keyless Access Control Unit, Electric Steering Lock, and TPMS Control Unit) Input Test (2016), or Keyless Access System (Keyless Access Control Unit, Electric Steering Lock, and TPMS Control Unit) Input Test (2017 2018 2019 2020),
   Test point 2	Body ground

   Is there battery voltage?

   YES 

   The IG1 SAFETY wire is OK. Go to step 4.

   NO 

   Repair an open or high resistance in the wire.

4. Open wire check (SGND lines)

   - 1. Turn the vehicle to the OFF (LOCK) mode

   - 2. Check for continuity between test points 1 and 2.

   Test condition	Vehicle OFF (LOCK) mode Keyless access/TPMS control unit connector A (32P): disconnected Keyless access/TPMS control unit connector B (36P): disconnected Keyless access/TPMS control unit connector C (20P): disconnected
   Test point 1	Keyless access/TPMS control unit connector A (32P) No. 17 - Refer to: Keyless Access System (Keyless Access Control Unit, Electric Steering Lock, and TPMS Control Unit) Input Test (2016), or Keyless Access System (Keyless Access Control Unit, Electric Steering Lock, and TPMS Control Unit) Input Test (2017 2018 2019 2020),
   Test point 2	Body ground

   Test point 1	Keyless access/TPMS control unit connector B (36P) No. 36 - Refer to: Keyless Access System (Keyless Access Control Unit, Electric Steering Lock, and TPMS Control Unit) Input Test (2016), or Keyless Access System (Keyless Access Control Unit, Electric Steering Lock, and TPMS Control Unit) Input Test (2017 2018 2019 2020),
   Test point 2	Body ground

   Is there continuity?

   YES 

   The SGND wires are OK. Go to step 5.

   NO 

   Repair an open or high resistance in the ground wire or poor ground (G501).

5. Open wire check (F-CAN A lines)

   - 1. Connect terminals A and B with a jumper wire.

   Terminal A	Keyless access/TPMS control unit connector C (20P) No. 2 - Refer to: Keyless Access System (Keyless Access Control Unit, Electric Steering Lock, and TPMS Control Unit) Input Test (2016), or Keyless Access System (Keyless Access Control Unit, Electric Steering Lock, and TPMS Control Unit) Input Test (2017 2018 2019 2020),
   Terminal B	Keyless access/TPMS control unit connector C (20P) No. 12 - Refer to: Keyless Access System (Keyless Access Control Unit, Electric Steering Lock, and TPMS Control Unit) Input Test (2016), or Keyless Access System (Keyless Access Control Unit, Electric Steering Lock, and TPMS Control Unit) Input Test (2017 2018 2019 2020),

   - 2. Disconnect the following connector.

   Gauge control module 32P connector

   - 3. Check for continuity between test points 1 and 2 respectively.

   Test condition	Vehicle OFF (LOCK) mode Keyless access/TPMS control unit connector A (32P): disconnected Keyless access/TPMS control unit connector B (36P): disconnected Keyless access/TPMS control unit connector C (20P): disconnected Gauge control module 32P connector: disconnected
   Test point 1	Gauge control module 32P connector No. 27 - Refer to: Gauge Control Module Input Test (2016), or Gauge Control Module Input Test (2017 2018 2019 2020)
   Test point 2	Gauge control module 32P connector No. 28 - Refer to: Gauge Control Module Input Test (2016), or Gauge Control Module Input Test (2017 2018 2019 2020)

   Is there continuity?

   YES 

   The F-CAN A wires are OK. Replace the gauge control module .

   NO 

   An open or poor connection in the F-CAN A wires between the keyless access/TPMS control unit and the gauge control module.