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Home >> Honda >> 2021 >> Pilot EX, AWD >> Repair and Diagnosis >> Body & Frame >> Door Locks >> Security System Keyless Entry System - Testing & Troubleshooting (1 Of 2) >> Check >> Keyless Access System Check
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Keyless Access System Check

1. Connect the HDS to the data link connector (DLC)

2. Turn the vehicle to the ON mode.

3. On the HDS screen, at SYSTEM SELECTION MENU, enter ONE-PUSH START, then select KEYLESS ACCESS CONTROL UNIT or BACKUP CONTROL UNIT.

NOTE:  If the HDS does not communicate, check the keyless access/TPMS control unit power, ground, K-line, and L-line connectors.

4. At KEYLESS ACCESS CONTROL UNIT, enter KEYLESS ACCESS SYSTEM INFORMATION, then select SYSTEM CHECK 1 or SYSTEM CHECK 2.

5. At BACKUP CONTROL UNIT, enter SYSTEM INFORMATION, then select SYSTEM CHECK.

6. If the HDS displays NORMAL N-1, the immobilizer system is OK at this time, refer to the STATUS LOG. If the HDS displays any other messages, check as follows:

System Check 1 (Keyless Access/TPMS Control Unit) 

System Check No. Possible cause Check items
A-1
A-2
A-3
G-4
  • Keyless remote is mismatched
  • LF interior antenna failure
  • Keyless remote is not registered
  • Keyless remote test
  • LF interior antenna test
  • Register the keyless remote
B-1
B-2
G-1
  • PCM is replaced
  • No communication between keyless access/TPMS control unit and PCM
  • Open in the IG1 line
  • Keyless access/TPMS control unit is replaced
  • Register the PCM
  • Check PCM
  • Check harness
  • Register the keyless access/TPMS control unit
C-1
C-2
G-2
G-3
  • MICU (Imoes unit) is replaced
  • Communication error between keyless access/TPMS control unit and MICU
  • Open in the IG1 VSA/ABS line
  • Keyless access/TPMS control unit is replaced
  • Register the keyless access/TPMS control unit
  • Check MICU
  • Check harness
C-3
C-4
  • Electric Steering Lock is replaced*1
  • Keyless access/TPMS control unit is replaced
  • Register the Keyless access/TPMS control unit
  • Register the electric steering lock*1
  • Check for an open or short in the wire IGN TRX lines*2
G-5
  • Electric steering lock is replaced*1
  • Keyless access/TPMS control unit is replaced
  • Register the keyless access/TPMS control unit
  • Register the electric steering lock*1
  • Check for an open or short in the wire IGN TRX lines*2

*1: With electric steering lock

*2: 9-speed A/T or with electric steering lock

System Check 2 (Keyless Access/TPMS Control Unit) 

System Check No. Possible cause Check items
D-1
D-2
D-3
  • S-NET line is short
  • No communication between keyless access/TPMS control unit and MICU (Imoes unit)
  • No communication between keyless access/TPMS control unit and PCM
  • Check harness
  • Check MICU
  • Check PCM
D-4
D-5
IGN TRX line trouble* Check IGN TRX line*

*: 9-speed A/T or with electric steering lock

System Check (Backup Control Unit) 

System Check No. Possible cause Check items
A-1
A-2
A-3
  • Keyless remote is mismatched
  • Engine start/stop switch failure
  • Keyless remote is not registered
  • Register the keyless remote
  • Check engine start/stop switch
B-1
B-2
  • PCM is replaced
  • Communication error between keyless access/TPMS control unit and PCM
  • Register the PCM
  • Check PCM
C-1
C-2
  • MICU is replaced
  • Communication error between keyless access/TPMS control unit and MICU (Imoes unit)
  • Open in the IG1 line
  • Register the keyless access/TPMS control unit
  • Check MICU
  • Check harness
D-1
D-2
D-3
  • S-NET line is short
  • No communication between keyless access/TPMS control unit and MICU (Imoes unit)
  • No communication between keyless access/TPMS control unit and PCM
  • Check harness
  • Check MICU
  • Check PCM
E-1
E-2
E-3
E-4
E-5
Keyless access/TPMS control unit is not registered Register the keyless access/TPMS control unit
F-1
F-2
F-3
F-4
F-5
Special Mode Turn the vehicle to the ON mode and then select the OFF (LOCK) mode with a registered keyless remote