DTC Troubleshooting: P2101 (L4) - Honda Accord CR/CT 2012-2017

DTC Troubleshooting: P2101

DTC P2101: ETCS Malfunction

Do not insert your fingers into the installed throttle body when you turn the ignition switch to ON (II)/press the engine start/stop button, or while the ignition switch is in ON (II)/the vehicle is in ON mode. If you do, you will seriously injure your fingers if the throttle valve is activated.

NOTE: Before you troubleshoot, record all freeze data and any on-board snapshot, and review the general troubleshooting information.

DTC Description	Confirmed DTC	Pending DTC	Freeze Frame
P2101 ETCS Malfunction

ETCS system check:

ETCS system check

?1.	Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode.

?2.	Clear the DTC with the HDS.

?3.	Select the ETCS TEST in the INSPECTION MENU with the HDS.

?4.

Check for Pending or Confirmed DTCs with the HDS.

DTC Description	Confirmed DTC	Pending DTC	Freeze Frame
P2101 ETCS Malfunction

Is DTC P2101 indicated?


	YES

The failure is duplicated. Go to step 3.


	NO

The failure is not duplicated. Go to step 2.

Problem verification:

Problem verification

?1.

Test-drive the vehicle for several minutes in the range of these recorded freeze data parameters:

	ENGINE SPEED
	VEHICLE SPEED
	APP SENSOR

Signal	Current conditions
Signal	Values	Unit
ENGINE SPEED
VEHICLE SPEED
APP SENSOR

?2.	Check for Pending or Confirmed DTCs with the HDS.

Is DTC P2101 indicated?


	YES

The failure is duplicated. Go to step 3.


	NO

Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the throttle body and the PCM.?

Determine possible failure area (throttle body, others):

Determine possible failure area (throttle body, others)

?1.	Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.

?2.	Disconnect the intake air duct from the throttle body.

?3.	Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode.

?4.	Clear the DTC with the HDS.

?5.	Visually check the throttle valve operation while doing the ETCS TEST in the INSPECTION MENU with the HDS.

Does the throttle valve operate smoothly?


	YES

Clean the throttle body, then do the repair verification. If DTC P2101 is indicated, replace the throttle body, then do the repair verification.


	NO

Go to step 4.

Open wire check (SG3 (DBW) line):

Open wire check (SG3 (DBW) line)

?1.	Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.

?2.	Jump the SCS line with the HDS.

?3.

Disconnect the following connectors.

PCM connector B (51P)

Throttle body 6P connector

?4.

Check for continuity between test points 1 and 2.

Test condition	IG LOCK (0) or OFF mode
	Throttle body 6P connector: disconnected
	PCM connector B (51P): disconnected
Test circuit	SG3 (DBW)
Test point 1	Throttle body 6P connector No. 3 (GRN)
Test point 2	PCM connector B (51P) No. 49 (GRN)

Is there continuity?


	YES

The SG3 (DBW) wire is OK. Go to step 5.


	NO

Repair an open in the SG3 (DBW) wire between the throttle body and the PCM (B49), then do the repair verification.

Open wire check (MTR1 line, MTR2 line):

Open wire check (MTR1 line, MTR2 line)

?1.

Disconnect the following connector.

PCM connector C (51P)

?2.

Connect terminals A and B with a jumper wire.

Terminal A	Throttle body 6P connector No. 1 (BLU/RED)
Terminal B	Throttle body 6P connector No. 2 (GRN/YEL)

?3.

Check for continuity between test points 1 and 2.

Test condition	IG LOCK (0) or OFF mode
	PCM connector B (51P): disconnected
	PCM connector C (51P): disconnected
	Throttle body 6P connector: disconnected
	Throttle body 6P connector No. 1 and No. 2: jumped
Test circuit	MTR1, MTR2
Test point 1	PCM connector C (51P) No. 11 (GRN/YEL)
Test point 2	PCM connector C (51P) No. 12 (BLU/RED)

Is there continuity?


	YES

The MTR1 and MTR2 wires are OK. Go to step 6.


	NO

Repair an open in the MTR1 wire or the MTR2 wire between the PCM (C11, C12) and the throttle body, then do the repair verification.

Throttle body internal circuit check:

Throttle body internal circuit check

?1.

At the throttle body side, measure the resistance between test points 1 and 2.

Test condition	IG LOCK (0) or OFF mode
	PCM connector B (51P): disconnected
	PCM connector C (51P): disconnected
	Throttle body 6P connector: disconnected
Test circuit	MTR1, MTR2
Test point 1	Throttle body 6P connector No. 1 (throttle body side)
Test point 2	Throttle body 6P connector No. 2 (throttle body side)

Is there about 1.0 k? or more?


	YES

Replace the throttle body, then do the repair verification.


	NO

The throttle body internal circuit is OK. Update the PCM if it does not have the latest software, or substitute a known-good PCM, then do the repair verification.

Repair verification:

?1.	Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.

?2.	Reconnect all connectors.

?3.	Exit the SCS mode with the HDS.

?4.	Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode.

?5.	Reset the PCM with the HDS.

?6.	Do the PCM idle learn procedure.

?7.

Test-drive the vehicle for several minutes in the range of these recorded freeze data parameters:

	ENGINE SPEED
	VEHICLE SPEED
	APP SENSOR

Signal	Current conditions
Signal	Values	Unit
ENGINE SPEED
VEHICLE SPEED
APP SENSOR

?8.	Check for Pending or Confirmed DTCs with the HDS.

Is DTC P2101 indicated?


	YES

Check for poor connections or loose terminals at the throttle body and the PCM, and clean the throttle body, then go to step 1. If the PCM was updated, substitute a known-good PCM, then recheck. If the PCM was substituted, go to step 1.


	NO

Troubleshooting is complete. If the PCM was substituted, replace the original PCM. If any other Pending or Confirmed DTCs are indicated, go to the indicated DTC's troubleshooting.?