Code P0141?

Hello,

The Direct Trouble Code[DTC] P0420 is the DTC that sets when your vehicle's catalytic converters efficiency has diminished to the point where it needs to be replaced, i.E. It's worn out. That is the reason the DTC came back after replacing the downstream O2 sensor and clearing the code. In the diagrams down below I have included the instructions for the removal and installation of the catalytic converter for your vehicle. Please go through this guide and report back with how everything turns out.

Thanks,
Alex
2CarPros

Hello again,

Sorry, I completely missed that the DTC number was P0141. In the diagrams down below I have included the diagnostic troubleshooting flowchart for DTC P0141 for your vehicle from the vehicle manufacturer. Please go through this guide and get back to us with what you find out.

Thanks,
Alex
2CarPros

Hello again,

I can't really see what the DTC's are on your code reader because of the glare on the screen. If you could type them in for me that would be better, and I would be happy to help you out with those. In the diagrams down below I have included the Power-train Management wiring diagrams for your vehicle with the Air Fuel Sensor[AF], a newer generation of an O2 sensor, which your vehicle uses, wires highlighted for you. Please get back to us with those DTC's and I hope this helps.

Thanks,
Alex
2CarPros

Hello again,

Okay, if you could please give me the DTC's from the code reader we can give you specific step by step flowchart guides from the vehicle manufacturer that will lead you directly to the problem for each DTC.

Thanks,
Alex
2CarPros

SCGRANTURISMO is one of our best! Glad you could get it fixed, that kind of problem can be tough. Please use 2CarPros anytime we are here to help.

Hi wyang46,

Both gets their power suply from the PGM-FI main relay, check if power is available.

Grounding is via PCM so check for broken wire circuits.

Hi Hi wyang46,

I have attached a testing procedure for you.

DTC P0135:
A/F SENSOR (SENSOR 1) HEATER CIRCUIT MALFUNCTION
NOTE: Before you troubleshoot, record all freeze data and any on-board snapshot, and review the general troubleshooting information

1. Turn the ignition switch ON (II).
2. Clear the DTC with the HDS.
3. Start the engine. Hold the engine speed at 3,000 rpm without load (in Park or neutral) until the radiator fan comes on, then let it idle.
4. Check for Temporary DTCs or DTCs with the HDS. Is DTC P0135 indicated?
YES - Go to step 5.
NO - Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the A/F sensor (Sensor 1), the PGM-FI subrelay, and the ECM/PCM.
5. Turn the ignition switch OFF.
6. Check the No. 11 FI SUB (15 A) fuse in the underhood fuse/relay box. Is the fuse OK?
YES - Go to step 7.
NO - Go to step 18.
7. Test the PGM-FI subrelay (E) in the under-hood fuse/relay box .

Fig. 26: Identifying PGM-FI Subrelay Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is the PGM-FI subrelay OK?
YES - Go to step 8.
NO - Replace the PGM-FI subrelay, then go to step 23.
8. Disconnect the A/F sensor (Sensor 1) 4P connector.
9. At the sensor side, measure resistance between A/F sensor (Sensor 1) 4P connector terminals No. 3 and No. 4.

Fig. 27: Measuring Resistance Between A/F Sensor (Sensor 1) 4P Connector Terminals No. 3 And No. 4 Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there 2.0-2.7 Ã © at room temperature?
YES - Go to step 10.
NO - Go to step 22.
10. At the sensor side, check for continuity between A/F sensor (Sensor 1) 4P connector terminals No. 1 and No. 3, and between terminals No. 1 and No. 4 individually.

Fig. 28: Checking For Continuity Between A/F Sensor 4P Connector Terminals No. 1 & No. 3 And Between Terminals No. 1 & No. 4 Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?
YES - Go to step 22.
NO - Go to step 11.
11. Jump the SCS line with the HDS.
12. Disconnect ECM/PCM connector C (44P).
13. Check for continuity between A/F sensor (Sensor 1) 4P connector terminal No. 3 and ECM/PCM connector terminal C9.

Fig. 29: Checking For Continuity Between A/F Sensor (Sensor 1) 4P Connector Terminal No. 3 And ECM/PCM Connector Terminal C9 Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?
YES - Go to step 14.
NO - Repair open in the wire between the ECM/PCM (C9) and the A/F sensor (Sensor 1), then go to step 23.
14. Remove the PGM-FI subrelay (E) from the underhood fuse/relay box.
15. Check for continuity between A/F sensor (Sensor 1) 4P connector terminal No. 4 and PGM-FI subrelay 4P connector terminal No. 2.

Fig. 31: Checking For Continuity Between A/F Sensor 4P Connector Terminal No. 4 And PGM-FI Subrelay 4P Connector Terminal No. 2

Hi wyang46,

If you want any information you can try getting an online shop manual at Mitchell1. Their data are quite comprehensive and since you are interested in tinkering with the car, that would be the best option.