DTC U1281, U128D(Keyless Access Power Control Unit)
DTC U1281 : Power control unit lost communication with MICU DTC U128D : Power control unit lost communication with gauge control module
NOTE:
- Refer to the DTC code shown on the display, and then inspect the connectors and terminals based on the instructions in the table below.
- The DTC may be stored due to the grounding failure or the power source failure at the transmitting control unit (the grounding inspection and the power source inspection on each control unit are required prior to this checking process).
| DTC Description | DTC |
|---|---|
| U1281 Power control unit lost communication with MICU | |
| U128D Power control unit lost communication with gauge control module |
DTCs (Power Control Unit)
NOTE: If you are troubleshooting multiple DTCs, be sure to follow the instructions in B-CAN System Diagnosis Test Mode A .
- 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 U1281 Power control unit lost communication with MICU DTC Description DTC U128D Power control unit lost communication with gauge control module Is DTC U1281 or U128D indicated?
YES
Go to step 2.
NO
Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the transmitting control units, and keyless access control unit.
- Open wire check (B-CAN_H, B-CAN_L lines)
-1. Turn the vehicle to the OFF (LOCK) mode.
-2. Disconnect the receiving control unit connector.
Keyless access control unit connector C (20P)
-3. Disconnect the transmitting control unit connectors.(Refer to the DTC code shown on the display, and then disconnect the connector(s) based on the instructions in the table below.)
Under-dash fuse/relay box connector H (20P) Gauge control module 32P connector -4. Check for continuity between the receiving control unit and the transmitting control unit on the B-CAN_H circuit and the B-CAN_L circuit as specified by the indicated DTC, and using the table below while in the vehicle OFF mode.
DTC CIRCUIT NAME RECEIVING CONTROL UNIT TRANSMITTING CONTROL UNIT U1281 Power control unit lost communication with MICU B-CAN_H Keyless access control unit connector C (20P) No. 1 Under-dash fuse/relay box connector H (20P) No. 12 B-CAN_L Keyless access control unit connector C (20P) No. 11 Under-dash fuse/relay box connector H (20P) No. 11 U128D Power control unit lost communication with gauge control module B-CAN_H Keyless access control unit connector C (20P) No. 1 Gauge control module 32P connector No. 23 B-CAN_L Keyless access control unit connector C (20P) No. 11 Gauge control module 32P connector No. 24 Is there continuity?
YES
The B-CAN_H and B-CAN_L wires are OK. Go to step 3.
NO
Repair an open in the B-CAN_H and/or B-CAN_L wires between the receiving control unit and the transmitting control unit.
- Determine possible failure area (the receiving control unit or the transmitting control unit)
-1. Reconnect the following connectors.
Keyless access control unit connector C (20P)Gauge control module 32P connectorUnder-dash fuse/relay box connector H (20P)
-2. Turn the vehicle to the ON mode.
-3. Clear the DTCs with the HDS.
-4. Turn the vehicle to the OFF (LOCK) mode and then the ON mode.
-5. Wait for at least 6 seconds.
-6. Check for DTCs with the HDS.
DTC Description DTC U1281 Power control unit lost communication with MICU U128D Power control unit lost communication with gauge control module Is DTC U1281 and U128D indicated?
YES
Replace the keyless access control unit .
NO
The keyless access control unit is OK at this time, replace the transmitting control unit.(Refer to the DTC code shown on the display, and then replace the control unit based on the instructions in the table below.)
DTC TRANSMITTING CONTROL UNIT U1281 Power control unit lost communication with MICU Under-dash fuse/relay box U128D Power control unit lost communication with gauge control module Gauge control module