Keyless Access System (Keyless Access Control Unit, Electric Steering Lock, and TPMS Control Unit) Input Test (2017 2018 2019 2020)

Keyless Access/TPMS Control Unit

NOTE:

Before testing, check for DTCs. If any DTCs are indicated, troubleshoot those DTCs first.
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 1 and Test Mode 2 (without the HDS) (2017 2018 2019 2020), or Body Electrical Troubleshooting - B-CAN System Diagnosis Test Mode B - Control Unit Not Communicating (2017 2018 2019 2020), or Body Electrical Troubleshooting - B-CAN System Diagnosis Test Mode A - Initial Communication and DTC Checks (2017 2018 2019 2020), or Body Electrical Troubleshooting - B-CAN System Diagnosis Test Mode A - Initial Communication and DTC Checks, or Body Electrical Troubleshooting - B-CAN System Diagnosis Test Mode B - Control Unit Not Communicating, or Body Electrical Troubleshooting - B-CAN System Diagnosis Test Mode C - No DTCs and Output Won't Shut OFF, .
Before testing, make sure the No. B4 (40 A), No. B2-6 (30 A)* 1, No. B3-2 (30 A), No. B3-5 (50 A), No. B3-7 (30 A) and the No. B8 (20 A* 1 / 10 A* 2) fuses in the main under-hood fuse box are OK.
Before testing, make sure the No. C16 (10 A) fuse in the under-hood fuse/relay box are OK.
Before testing, make sure the No. D11 (7.5 A)* 1, No. D13 (7.5 A), No. D18 (10 A), and the No. D23 (7.5 A) fuses in the driver's under-dash fuse/relay box are OK.
Some models have the rear outer handle touch sensor. Perform the troubleshooting flow where applicable.
With auto idle stop system: Before testing, make sure the No. H7 (10 A) fuse in the auxiliary under-dash fuse/relay box is OK.

*1: Without auto idle stop system:2: With auto idle stop system

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

2. Disconnect the keyless access/TPMS control unit connectors.

Keyless access/TPMS control unit connector A (32P) (female terminals): Keyless access/TPMS control unit connector B (36P) (female terminals): Keyless access/TPMS control unit connector C (20P) (female terminals):

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

3. Inspect the connectors and socket terminals to be sure they are all making good contact:

If the terminals are bent, loose, or corroded, repair them as necessary, and recheck the system.
If the terminals look OK, go to step 4.

4. With the connectors still disconnected, do the following input tests:

If any test indicates a problem, find and correct the cause, then recheck the system.
If all the input tests prove OK, then go to step 5.

Cavity	Wire	Test condition	Test: Desired result	Possible cause if desired result is not obtained
C4	LT BLU	Under all conditions	Check for continuity between terminal C4 and data link connector (DLC) terminal No. 7:There should be continuity.	An open or high resistance in the K-LINE wire
C4	LT BLU	Under all conditions	Check for continuity between terminal C4 and body ground:There should be no continuity.	A short to ground in the K-LINE wire
C6	BLU	Under all conditions	Check for continuity between terminal C4 and data link connector (DLC) terminal No. 15:There should be continuity.	An open or high resistance in the P-LINE wire
C6	BLU	Under all conditions	Check for continuity between terminal C6 and body ground:There should be no continuity.	A short to ground in the P-LINE wire

Cavity	Wire	Test condition	Test: Desired result	Possible cause if desired result is not obtained
B10	BLK	Press the engine start/stop button	Measure the voltage to ground:There should be battery voltage.	Blown No. D18 (10 A) fuse in the driver's under-dash fuse/relay box Faulty driver's under-dash fuse/relay box Faulty engine start/stop switch An open or high resistance in the wire
B11	GRY	Press the engine start/stop button	Check for continuity to ground:There should be continuity.	Faulty keyless access/TPMS control unit Faulty engine start/stop switch An open or high resistance in the wire
C5	PUR	Jump the SCS line with the HDS, disconnect PCM connector A (51P)	Check for continuity between terminal driver's under-dash fuse/relay box connector F (32P) terminal No. 18 and PCM connector A (51P) terminal No. 38:There should be continuity.	An open in the S-NET wire PCM
		Disconnect the driver's under-dash fuse/relay box connector G (16P)	Check for continuity between terminal C5 and driver's under-dash fuse/relay box connector G (16P) terminal No. 12:There should be continuity.	An open in the S-NET wire Faulty driver's under-dash fuse/relay box
			Check for continuity between terminal C5 and body ground:There should be no continuity.	A short to ground in the S-NET wire

5. Reconnect the connectors, and do the following input tests:

If any test indicates a problem, find and correct the cause, then recheck the system.
If all the input tests prove OK, then go to step 6.

Cavity	Wire	Test condition	Test: Desired result	Possible cause if desired result is not obtained
A1	RED	Under all conditions	Measure the voltage to ground:There should be battery voltage.	Blown No. D18 (10 A) fuse in the driver's under-dash fuse/relay box Faulty driver's under-dash fuse/relay box An open or high resistance in the wire
B18	GRN	Under all conditions	Measure the voltage to ground:There should be battery voltage.	Blown No. C16 (10 A) fuse in the under-hood fuse/relay box Faulty under-hood fuse/relay box An open or high resistance in the wire
A17	BRN	In all power modes	Measure the voltage to ground:There should be less than 0.2 V.	Poor ground (G501) An open or high resistance in the ground wire
B36	BRN	In all power modes	Measure the voltage to ground:There should be less than 0.2 V.	Poor ground (G501) An open or high resistance in the ground wire

*1: Without auto idle stop system *2: With auto idle stop system *3: With electric steering lock

Cavity	Wire	Test condition	Test: Desired result	Possible cause if desired result is not obtained
B30	BRN	Vehicle ON mode	Measure the voltage to ground:There should be battery voltage.	Blown No. B3-2 (30 A) fuse in the main under-hood fuse box Faulty under-dash subrelay box An open or high resistance in the wire
B34	BLU	Vehicle ON mode	Measure the voltage to ground:There should be battery voltage.	Blown No. D23 (7.5 A) fuse in the driver's under-dash fuse/relay box Faulty driver's under-dash fuse/relay box Faulty under-dash subrelay box An open or high resistance in the wire
B29	RED	Vehicle ON mode	Measure the voltage to ground:There should be battery voltage.	Blown No. B3-7 (30 A) fuse in the main under-hood fuse box Faulty under-dash subrelay box An open or high resistance in the wire
B27	LT GRN	Vehicle ON mode	Measure the voltage to ground:There should be battery voltage.	Blown No. B3-2 (30 A) fuse in the main under-hood fuse box Faulty under-dash subrelay box An open or high resistance in the wire
C14	WHT	Driver's door outer handle lock button pressed	Measure the voltage to ground:There should be less than 0.2 V.	Faulty driver's door outer handle Poor ground (G501) or an open in the ground wire An open or high resistance in the wire
C14	WHT	Driver's door outer handle lock button released	Measure the voltage to ground:There should be about 5 V.	Faulty driver's door outer handle A short to ground in the wire
C13	YEL	Front passenger's door outer handle lock button pressed	Measure the voltage to ground:There should be less than 0.2 V.	Faulty front passenger's door outer handle Poor ground (G507) or an open in the ground wire An open or high resistance in the wire
C13	YEL	Front passenger's door outer handle lock button released	Measure the voltage to ground:There should be about 5 V.	Faulty front passenger's door outer handle A short to ground in the wire
C7	WHT	Left rear door outer handle lock button pressed	Measure the voltage to ground:There should be less than 0.2 V.	Faulty left rear door outer handle Poor ground (G602) or an open in the ground wire An open or high resistance in the wire
C7	WHT	Left rear door outer handle lock button released	Measure the voltage to ground:There should be about 5 V.	Faulty left rear door outer handle A short to ground in the wire

*1: Without auto idle stop system*2: With auto idle stop system*3: With electric steering lock

Cavity	Wire	Test condition	Test: Desired result	Possible cause if desired result is not obtained
C8	LT GRN	Right rear door outer handle lock button pressed	Measure the voltage to ground:There should be less than 0.2 V.	Faulty right rear door outer handle Poor ground (G604) or an open in the ground wire An open or high resistance in the wire
C8	LT GRN	Right rear door outer handle lock button released	Measure the voltage to ground:There should be about 5 V.	Faulty right rear door outer handle A short to ground in the wire
B1	PNK	Electric parking brake switch pressed (apply)	Check for continuity to ground:There should be continuity	Faulty electric parking brake switch Faulty electric parking brake switch ground An open or high resistance in the wire
B1	PNK	Brake pedal pressed and electric parking brake switch pushed (released)	Check for continuity to ground:There should be no continuity.	Faulty electric parking brake switch A short to ground in the wire
C16	YEL	Power tailgate outer handle switch pressed	Measure the voltage to ground:There should be less than 0.2 V.	Faulty power tailgate outer handle switch Faulty rearview camera unit Faulty power tailgate control unit An open or high resistance in the wire
C16	YEL	Power tailgate outer handle switch released	Measure the voltage to ground:There should be about 5 V.	Faulty power tailgate outer handle switch A short to ground in the wire
C10	LT GRN	Shift position/mode in P	Check for continuity to ground: There should be continuity.	Faulty TCM Faulty SBW shifter control module Faulty driver's under-dash fuse/relay box An open or high resistance in the wire
C10	LT GRN	Shift position/mode in any position other than P	Check for continuity to ground:There should be no continuity.	Faulty TCM Faulty SBW shifter control module A short to ground in the wire
B19	PUR	Brake pedal pressed	Measure the voltage to ground:There should be battery voltage.	Blown No. B2-6 (30 A) fuse in the main under-hood fuse/relay box Blown No. B8 (20 A* 1 / 10 A* 2) fuse in the main under-hood fuse/relay box Faulty DC-DC converter* 2 Faulty brake pedal position switch An open or high resistance in the wire A short to ground in the wire
B19	PUR	Brake pedal released	Measure the voltage to ground:There should be less than 0.2 V.	Faulty brake pedal position switch

*1: Without auto idle stop system*2: With auto idle stop system*3: With electric steering lock

Cavity	Wire	Test condition	Test: Desired result	Possible cause if desired result is not obtained
B3* 3	RED	Electric steering lock (LOCK)	Measure the voltage to ground:There should be about 5 V.	Faulty electric steering lock A short to ground in the wire
B3* 3	RED	Electric steering lock (UNLOCK)	Measure the voltage to ground:There should be less than 0.2 V.	Faulty electric steering lock An open or high resistance in the wire

*1: Without auto idle stop system*2: With auto idle stop system*3: With electric steering lock

Electric Steering Lock (with electric steering lock)

NOTE:

SRS components are located in this area. Review the SRS component locations - Refer to: SRS Component Location Index, or SRS Component Location Index (2017 2018 2019 2020) , and precautions and procedures before doing repairs or servicing.
Before testing, check for DTCs. If any DTCs are indicated, troubleshoot those DTCs first.

6. Turn the vehicle to the OFF (LOCK) mode.

7. Disconnect the electric steering lock 12P connector.

Electric steering lock 12P connector

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

8. Inspect the connector and socket terminals to be sure they are all making good contact:

If the terminals are bent, loose, or corroded, repair them as necessary, and recheck the system.
If the terminals look OK, then go to step 9.

9. Reconnect the connector, and do the following input tests:

If any test indicates a problem, find and correct the cause, then recheck the system.
If all the input tests prove OK, go to step 10.

Cavity	Wire	Test condition	Test: Desired result	Possible cause if desired result is not obtained
3	RED	Under all conditions	Measure the voltage to ground:There should be battery voltage.	Blown No. D18 (10 A) fuse in the driver's under-dash fuse/relay box Faulty driver's under-dash fuse/relay box An open or high resistance in the wire

Cavity	Wire	Test condition	Test: Desired result	Possible cause if desired result is not obtained
12	BLU	Vehicle ON mode	Measure the voltage to ground:There should be battery voltage.	Blown No. D23 (7.5 A) fuse in the driver's under-dash fuse/relay box Faulty driver's under-dash fuse/relay box Faulty under-dash subrelay box An open or high resistance in the wire
7	BRN	In all power modes	Measure the voltage to ground:There should be less than 0.2 V.	Poor ground (G501) An open or high resistance in the ground wire
8	RED	Electric steering lock (LOCK)	Measure the voltage to ground:There should be about 5 V.	Faulty keyless access/TPMS control unit A short to ground in the wire An open or high resistance in the wire
8	RED	Electric steering lock (UNLOCK)	Measure the voltage to ground:There should be less than 0.2 V.	Faulty electric steering lock
5	PNK	Vehicle ON mode	Measure the voltage to ground:There should be battery voltage.	Faulty keyless access/TPMS control unit An open or high resistance in the wire A short to ground in the wire

10. If multiple failures are found on more than one control unit, replace the keyless access/TPMS control unit .

If input failures are related to a particular control unit, replace the control unit.