Hi all. This is going to be my first post here, thanks for contributing.

So i just got myself an 04 accord and I would appreciate getting some suggestions about a few issues im having.

Essentially i have two fault codes and one symptom that seems completely unrelated to the faults.


Let's start with the symptom. -my temperature gauge goes above mid point and fluctuates between mid and 3/4.
The Rad fan doesn't seem to kick in at 1/2 and the fans for the AC and Rad kick in when i turn on the AC.
I have a new fan relay on the way... Hoping that fixes that but I'm not sure.

The oil is clean and no signs of blown head.
Coolant levels are fine too, but i haven't located the secondary coolant tank nor tested Rad pressure. As first point is getting the fan to spin i imagine.

The car does also struggle a little bit with cold start as of recent i think that might be related to the other codes which are.

P0141 - P0141 - H02S S2 Heater Circuit Malfunction Secondary heated Oxygen sensor.


P2228 - Barometric pressure circuit low


Not sure how/if these faults link up.
i have limited knowledge of cars but am willing to attempt basic / intermediate fixes before hitting a mechanic to take over.
Thanks ^^

 

Replacing the relay won't help, because you verified the relay works when both fans run when you turn on the a/c.

Do your fans ever turn on when the temperature rises and the a/c is turned off? Are you losing any coolant or have to add coolant?

Was any work recently done on your car?

P0141 is an error for the heater circuit in the downstream O2 sensor bolted into the catalytic converter. The cause can be a bad O2 sensor, the wiring, or the PCM.

P2228 is a code for the barometric pressure. The baro sensor is part of the PCM. You can take a look at the PCM's electrical connectors to see if you have any loose pins or corrosion.

 

Hi mate, thanks for the response. To confirm yes the fans spin fine when ac is on. And to my knowledge no the dad can doesn't come on when the engine is at temp.
I only just got the car so I'm not sure about the recent work but I think she had been sitting for a few months at leAst.
Went for a drive today for about 3 hours and the temp gauge sits just a fraction above half way when going above 30mph.

Stop start traffic and it rises to just below 3/4.

 

If you turn on the a/c when the gauge approaches 3/4, does the temperature return to normal?

 

So if the gauge goes to 3/4, in stop start traffic for instance, and I put the ac on to get some airflow the gauge will return to just over 1/2 like in that previous pic.


What does this mean to you.

Also, are you sure the relay isn't an idea? Reason being - this model has a relay for AC condencer fan and rad fan.
and only when ac is on do both fans kick in.

 

Each relay operates one fan. The names of the fans/relays are misleading. Both fans run to cool down the radiator and a/c condenser. Both relays are working, because both fans run.

The place I would look is the radiator fan switch that is on the bottom of the radiator. It will have 2 wires and looking at my TSX wiring diagram, the wires should be green and black. Your UK accord may be different. Look for obvious damage to the wiring and corrosion in that connector, because it is exposed to the elements. To be sure you have a bad sensor, unplug the sensor with the engine running, and short the connector with a piece of wire. If the fans turn on, then you verified you need a new radiator fan switch.

 

Noted, I will have a look in the next day or two. I tried to look today but saw I have to take the engine cover off to get to the rad.
so I'll try get it off tomorrow.

Thanks for the advice about next steps, much appreciated.