DTC B1627 (2017 2018 2019 2020)

DTC B1627  : RF1 Unit disconnected (2-way transceiver or RF antenna disconnected)

DTC (Keyless Access Control Unit)

1. Problem verification

   -1. Clear the DTCs with the HDS.

   - 2. Select KEYLESS ACCESS CONTROL UNIT from the ONE-PUSH START system select menu with the HDS, and enter SELF CHECK.

   One-Push - KEYLESS ACCESS CONTROL UNIT - SELF CHECK

   Check for DTCs with the HDS.

   DTC Description	DTC
   B1627 RF1 Unit disconnected (2-way transceiver or RF antenna disconnected)

   Is DTC B1627 indicated?

   YES 

   Go to step 2.

   NO 

   Intermittent failure, the system is OK at this time.

2. Shorted wire check (RF TRX PWR, RF TRX GND, RF TRX UART lines)

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

   - 2. Disconnect the following connectors.

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

   2-way transceiver connector A (3P)

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

   Test condition	Vehicle OFF (LOCK) modeKeyless access/TPMS control unit connector A (32P): disconnected2-way transceiver connector A (3P): disconnected
   Test point 1	Keyless access/TPMS control unit connector A (32P) (female terminals) No. 4:
   Test point 2	Body ground

   Test point 1	Keyless access/TPMS control unit connector A (32P) (female terminals) No. 5:
   Test point 2	Body ground

   Test point 1	Keyless access/TPMS control unit connector A (32P) (female terminals) No. 6:
   Test point 2	Body ground

   Courtesy of HONDA, U.S.A., INC.

   Is there continuity?

   YES 

   Repair a short to ground in the wire.

   NO 

   The RF TRX PWR, RF TRX GND, and RF TRX UART wires are not shorted. Go to step 3.

3. Open wire check (RF TRX PWR, RF TRX GND, RF TRX UART lines)

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

   Terminal A	2-way transceiver connector A (3P) (female terminals) No. 1:
   Terminal B	Body ground

   Terminal A	2-way transceiver connector A (3P) (female terminals) No. 2:
   Terminal B	Body ground

   Terminal A	2-way transceiver connector A (3P) (female terminals) No. 3:
   Terminal B	Body ground

   Courtesy of HONDA, U.S.A., INC.

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

   Test condition	Vehicle OFF (LOCK) modeKeyless access/TPMS control unit connector A (32P): disconnected2-way transceiver connector A (3P): disconnected
   Test point 1	Keyless access/TPMS control unit connector A (32P) (female terminals) No. 4:
   Test point 2	Body ground

   Test point 1	Keyless access/TPMS control unit connector A (32P) (female terminals) No. 5:
   Test point 2	Body ground

   Test point 1	Keyless access/TPMS control unit connector A (32P) (female terminals) No. 6:
   Test point 2	Body ground

   Courtesy of HONDA, U.S.A., INC.

   Is there continuity?

   YES 

   The RF TRX PWR, RF TRX GND, and RF TRX UART wires are OK. Go to step 4.

   NO 

   Repair an open or high resistance in the wire.

4. 2-way transceiver check (substitution)

   -1. Substitute a known good 2-way transceiver.

   - 2. Reconnect the following connectors.

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

   2-way transceiver connector A (3P)

   - 3. Clear the DTCs with the HDS.

   - 4. Select KEYLESS ACCESS CONTROL UNIT from the ONE-PUSH START system select menu with the HDS, and enter SELF CHECK.

   One-Push - KEYLESS ACCESS CONTROL UNIT - SELF CHECK

   Check for DTCs with the HDS.

   DTC Description	DTC
   B1627 RF1 Unit disconnected (2-way transceiver or RF antenna)

   Is DTC B1627 indicated?

   YES 

   Replace the roof antenna (built into the XM antenna) .

   NO 

   Replace the original 2-way transceiver .