Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
DTC U0100: Power Control Unit Lost Communication With PCM (V6, Keyless Access Power Control Unit with CAN gateway) (2015-17)
| DTC Description | DTC |
|---|---|
| U0100 Power control unit lost communication with PCM |
DTC (Power Control Unit)
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 (L4), or How to Troubleshoot the Dual Clutch Transmission (DCT), or How to Troubleshoot the Brake Booster Pressure Monitoring System (With Auto Idle Stop System), or How to Troubleshoot the Fuel and Emissions Systems (V6, Without Auto Idle Stop System), or How to Troubleshoot the Fuel and Emissions Systems (V6, With Auto Idle Stop System) .
- CAN gateway system DTC check
-1. Check for CAN gateway system DTCs with the HDS.
DTC Description DTC U0029-00 CAN Gateway F-CAN ch A Bus Off U0047-00 CAN Gateway F-CAN ch B Bus Off U3000-49 CAN Gateway Internal Failure Is DTC U0029-00, U0047-00, and/or U3000-49 indicated?
YES
Go to the troubleshooting for CAN gateway system DTC (s) - Refer to: Communication Systems DTC Troubleshooting Index (V6, With CAN gateway) (2015-17) or Communication Systems DTC Troubleshooting Index (2018-19) .
NO
Go to step 2.
- F-CAN circuit communication check
-1. Select the FUNCTION TEST in the CAN gateway with the HDS, then select the F-CAN Bus Connected Unit Check.
F-CAN Bus Connected Unit Check
Which result is indicated?
PCM (Bus A) is Not Available
Go to step 3.
PCM (Bus B) is Not Available
Go to step 5. Refer to: 5
KEYLESS ACCESS/TPMS CONTROL UNIT (Bus B) is Not Available
Go to step 7. Refer to: 7
PCM and KEYLESS ACCESS/TPMS CONTROL UNIT are Detected
Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the keyless access/TPMS control unit, the CAN gateway, and the PCM.
- Open wire check (F-CAN A_H line)
-1. Turn the vehicle to the OFF (LOCK) mode.
- 2. Jump the SCS line with the HDS.
- 3. Disconnect the following connectors.
CAN gateway 24P connector PCM connector A (51P) - 4. Check for continuity between test points 1 and 2.
Test condition Vehicle OFF (LOCK) mode CAN gateway 24P connector: disconnected PCM connector A (51P): disconnected Test point 1 CAN gateway 24P connector No. 14 Test point 2 PCM connector A (51P) No. 9 - Refer to: PCM Connector for Inputs and Outputs (L4) (2015-17) or PCM Connector for Inputs and Outputs (V6, Without Auto Idle Stop System) (2015-17) or PCM Connector for Inputs and Outputs (V6, With Auto Idle Stop System) (2015-17) or PCM Connector for Inputs and Outputs (L4) (2018-19), or PCM Connector for Inputs and Outputs (V6) (2018-19) Is there continuity?
YES
The F-CAN A_H wire is OK. Go to step 4.
NO
Repair an open in the F-CAN A_H wire between the PCM (A9) and the CAN gateway.
- Open wire check (F-CAN A_L line)
-1. Check for continuity between test points 1 and 2.
Test condition Vehicle OFF (LOCK) mode CAN gateway 24P connector: disconnected PCM connector A (51P): disconnected Test point 1 CAN gateway 24P connector No. 15 Test point 2 PCM connector A (51P) No. 10 - Refer to: PCM Connector for Inputs and Outputs (L4) (2015-17) or PCM Connector for Inputs and Outputs (V6, Without Auto Idle Stop System) (2015-17) or PCM Connector for Inputs and Outputs (V6, With Auto Idle Stop System) (2015-17) or PCM Connector for Inputs and Outputs (L4) (2018-19), or PCM Connector for Inputs and Outputs (V6) (2018-19) Is there continuity?
YES
The F-CAN A_L wire is OK. Check for poor connections or loose terminals at the CAN gateway and the PCM. Update the PCM if it does not have the latest software, or substitute a known-good PCM - Refer to: PCM Removal and Installation (With SH-AWD), or PCM Removal and Installation (Without SH-AWD) , then recheck. If DTC U0100 goes away and the PCM was updated, troubleshooting is complete. If DTC U0100 goes away and the PCM was substituted, replace the original PCM - Refer to: PCM Removal and Installation (With SH-AWD), or PCM Removal and Installation (Without SH-AWD) .
NO
Repair an open in the F-CAN A_L wire between the PCM (A10) and the CAN gateway.
- Open wire check (F-CAN B_H line)
-1. Turn the vehicle to the OFF (LOCK) mode.
- 2. Jump the SCS line with the HDS.
- 3. Disconnect the following connectors.
CAN gateway 24P connector PCM connector A (51P) - 4. Check for continuity between test points 1 and 2.
Test condition Vehicle OFF (LOCK) mode CAN gateway 24P connector: disconnected PCM connector A (51P): disconnected Test point 1 CAN gateway 24P connector No. 11 Test point 2 PCM connector A (51P) No. 11 - Refer to: PCM Connector for Inputs and Outputs (L4) (2015-17) or PCM Connector for Inputs and Outputs (V6, Without Auto Idle Stop System) (2015-17) or PCM Connector for Inputs and Outputs (V6, With Auto Idle Stop System) (2015-17) or PCM Connector for Inputs and Outputs (L4) (2018-19), or PCM Connector for Inputs and Outputs (V6) (2018-19) Is there continuity?
YES
The F-CAN B_H wire is OK. Go to step 6.
NO
Repair an open in the F-CAN B_H wire between the PCM (A11) and the CAN gateway.
- Open wire check (F-CAN B_L line)
-1. Check for continuity between test points 1 and 2.
Test condition Vehicle OFF (LOCK) mode CAN gateway 24P connector: disconnected PCM connector A (51P): disconnected Test point 1 CAN gateway 24P connector No. 10 Test point 2 PCM connector A (51P) No. 12 - Refer to: PCM Connector for Inputs and Outputs (L4) (2015-17) or PCM Connector for Inputs and Outputs (V6, Without Auto Idle Stop System) (2015-17) or PCM Connector for Inputs and Outputs (V6, With Auto Idle Stop System) (2015-17) or PCM Connector for Inputs and Outputs (L4) (2018-19), or PCM Connector for Inputs and Outputs (V6) (2018-19) Is there continuity?
YES
The F-CAN B_L wire is OK. Check for poor connections or loose terminals at the CAN gateway and the PCM. Update the PCM if it does not have the latest software, or substitute a known-good PCM - Refer to: PCM Removal and Installation (With SH-AWD), or PCM Removal and Installation (Without SH-AWD) , then recheck. If DTC U0100 goes away and the PCM was updated, troubleshooting is complete. If DTC U0100 is not indicated the PCM was substituted, replace the original PCM - Refer to: PCM Removal and Installation (With SH-AWD), or PCM Removal and Installation (Without SH-AWD) .
NO
Repair an open in the F-CAN B_L wire between the PCM (A12) and the CAN gateway.
- Open wire check (F-CAN B_H line)
-1. Turn the vehicle to the OFF (LOCK) mode.
- 2. Disconnect the following connectors.
CAN gateway 24P connector Keyless access/TPMS control unit connector C (20P) - 3. Check for continuity between test points 1 and 2.
Test condition Vehicle OFF (LOCK) mode CAN gateway 24P connector: disconnected Keyless access/TPMS control unit connector C (20P): disconnected Test point 1 CAN gateway 24P connector No. 11 Test point 2 Keyless access/TPMS control unit connector C (20P) No. 2 Is there continuity?
YES
The F-CAN B_H wire is OK. Go to step 8.
NO
Repair an open in the F-CAN B_H wire between the CAN gateway and the keyless access/TPMS control unit.
- Open wire check (F-CAN B_L line)
-1. Check for continuity between test points 1 and 2.
Test condition Vehicle OFF (LOCK) mode CAN gateway 24P connector: disconnected Keyless access/TPMS control unit connector C (20P): disconnected Test point 1 CAN gateway 24P connector No. 10 Test point 2 Keyless access/TPMS control unit connector C (20P) No. 12 Is there continuity?
YES
The F-CAN B_L wire is OK. Check for poor connections or loose terminals at the CAN gateway and the keyless access/TPMS control unit. Substitute a good-known keyless access/TPMS control unit , then recheck. If DTC U0100 is not indicated the keyless access/TPMS control unit was substituted, replace the original keyless access/TPMS control unit .
NO
Repair an open in the F-CAN B_L wire between the CAN gateway and the keyless access/TPMS control unit.
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
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