DTC Troubleshooting: P1659 (L4) - Honda Accord CR/CT 2012-2017

1.

Problem verification:

Problem verification

?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.

Check for Pending or Confirmed DTCs with the HDS.

DTC Description	Confirmed DTC	Pending DTC	Freeze Frame
P1659 ETCS Control Relay OFF Malfunction

Is DTC P1659 indicated?


	YES

The failure is duplicated. Go to step 2.


	NO

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

2.

Determine possible failure area (+B DBW, DBW RLY OUT/VBDBW line, or others):

Determine possible failure area (+B DBW, DBW RLY OUT/VBDBW line, or others)

?1.	Turn the ignition switch to LOCK (0).

?2.

Check the following fuse.

Fuse	No. A18 (15 A)
Location	Under-hood fuse/relay box

Is the fuse OK?


	YES

Go to step 3.


	NO

Go to step 8.

3.

ETCS control relay test:

ETCS control relay test

?1.	Remove the ETCS control relay (A) from the under-hood fuse/relay box.

?2.	Test the ETCS control relay.

Is the ETCS control relay OK?


	YES

The ETCS control relay is OK. Go to step 4.


	NO

Replace the ETCS control relay, then do the repair verification.

4.

Determine possible failure area (under-hood fuse/relay box, others):

Determine possible failure area (under-hood fuse/relay box, others)

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

?2.

Measure the voltage between test points 1 and 2.

Test condition	IG ON (II) or ON mode
	ETCS control relay: disconnected
Test circuit	FI MAIN RLY OUT
Test point 1	ETCS control relay 4P socket No. 3
Test point 2	Body ground

Is there battery voltage?


	YES

Go to step 5.


	NO

Replace the under-hood fuse/relay box, then do the repair verification.

5.

Open wire check (+B DBW line):

Open wire check (+B DBW line)

?1.

Measure the voltage between test points 1 and 2.

Test condition	IG ON (II) or ON mode
	ETCS control relay: disconnected
Test circuit	+B DBW
Test point 1	ETCS control relay 4P socket No. 1
Test point 2	Body ground

Is there battery voltage?


	YES

The +B DBW wire is OK. Go to step 6.


	NO

Repair an open in the +B DBW wire between the No. A18 (15 A) fuse and the ETCS control relay, or replace the under-hood fuse/relay box, then do the repair verification.

6.

Open wire check (DBW RLY OUT/VBDBW line):

Open wire check (DBW RLY OUT/VBDBW 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 connector.

PCM connector C (51P)

?4.

Check for continuity between test points 1 and 2.

Test condition	IG LOCK (0) or OFF mode
	ETCS control relay: disconnected
	PCM connector C (51P): disconnected
Test circuit	DBW RLY OUT/VBDBW
Test point 1	ETCS control relay 4P socket No. 2
Test point 2	PCM connector C (51P) No. 2 (YEL/GRN)

Is there continuity?


	YES

The DBW RLY OUT/VBDBW wire is OK. Go to step 7.


	NO

Repair an open in the DBW RLY OUT/VBDBW wire between the PCM (C2) and the ETCS control relay, then do the repair verification.

7.

Open wire check (DBW RLY CL- line):

Open wire check (DBW RLY CL- line)

?1.

Disconnect the following connector.

PCM connector A (51P)

?2.

Check for continuity between test points 1 and 2.

Test condition	IG LOCK (0) or OFF mode
	ETCS control relay: disconnected
	PCM connector C (51P): disconnected
	PCM connector A (51P): disconnected
Test circuit	DBW RLY CL-
Test point 1	ETCS control relay 4P socket No. 4
Test point 2	PCM connector A (51P) No. 19 (WHT)

Is there continuity?


	YES

The DBW RLY CL- wire is OK. Update the PCM if it does not have the latest software, or substitute a known-good PCM, then do the repair verification.


	NO

Repair an open in the DBW RLY CL- wire between the PCM (A19) and the ETCS control relay, then do the repair verification.

8.

Shorted wire check (DBW RLY OUT/VBDBW line):

Shorted wire check (DBW RLY OUT/VBDBW line)

?1.	Remove the ETCS control relay (A) from the under-hood fuse/relay box.

?2.	Jump the SCS line with the HDS.

?3.

Disconnect the following connector.

PCM connector C (51P)

?4.

Check for continuity between test points 1 and 2.

Test condition	IG LOCK (0) or OFF mode
	ETCS control relay: disconnected
	PCM connector C (51P): disconnected
Test circuit	VBDBW
Test point 1	PCM connector C (51P) No. 2 (YEL/GRN)
Test point 2	Body ground

Is there continuity?


	YES

Repair a short in the DBW RLY OUT/VBDBW wire between the PCM (C2) and the ETCS control relay, then do the repair verification.


	NO

The DBW RLY OUT/VBDBW wires are OK. Go to step 9.

9.

Determine possible failure area (+B DBW line, PCM):

Determine possible failure area (+B DBW line, PCM)

?1.

Check for continuity between test points 1 and 2.

Test condition	IG LOCK (0) or OFF mode
	ETCS control relay: disconnected
	PCM connector C (51P): disconnected
Test circuit	+B DBW
Test point 1	ETCS control relay 4P socket No. 1
Test point 2	Body ground

Is there continuity?


	YES

Repair a short in the +B DBW wire between the No. A18 (15 A) fuse and the ETCS control relay, or replace the under-hood fuse/relay box, then do the repair verification.


	NO

The +B DBW wire 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.

Check for Pending or Confirmed DTCs with the HDS.

DTC Description	Confirmed DTC	Pending DTC	Freeze Frame
P1659 ETCS Control Relay OFF Malfunction

Is DTC P1659 indicated?


	YES

Check for poor connections or loose terminals at the ETCS control relay and the PCM. 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.?