Hey everybody,
My first post, I tried search and learned a lot, but now I'm at the point where I can't find anything relevant.

2004 manual GT with 35,500 km

I bought this car a couple weeks ago and it runs great. Just one problem. My CEL is on. I pulled the code P0410 (air pump). I checked the fuse and it was blown, so I thought, "sweet." I'll just replace the fuse and the problem will be solved. After replacing the fuse I cleared the code but the CEL came back with the same P0410 code. I tested the air pump by supplying power direct from the battery (I hope that's an ok way to test it). It came on but was very weak, then it slowed down and stopped. It wouldn't respond after that. I decided to check the fuse again and sure enough, the new fuse was blown.

So, my questions are:

1. Is my air pump ok? Is the way I tested it ok or did I fry it?
2. I have another 60amp fuse, should I replace it or is it obvious that I have an electrical problem and it will just blow again anyway?
3. What should I do next? Take it to the dealer for diagnostic?
4. Are there any other tests I can perform to narrow the problem down?


I bought this car with a remote starter/alarm already installed. I mention this only because I've owned cars in the past where I had a remote starter installed and it caused weird electical problems.

Any help/advice would be greatly appreciated.
Thanks

-Matt

 

If you keep blowing the 60A fuse, I would start tracing down the wiring from the motor.
Between the motor and fuse there is a relay which is in the PCM box:


Make sure nothing is being shorted... I would even disconnect/reconnect the relay.

If you can't find anything being shorted, you can always disconnect the harness from the air pump and see if the fuse still blows.
This will eliminate the pump itself and help narrow it down.

 

Thanks, I'll give that a try.

 

Ok so here's what I did.

1. I opened up the pcm box and disconnected/reconnected the air pump relay.
2. I put it all back together, disconnected the air pump, put a new fuse in and turned the key to "on". Checked fuse, fuse ok.
3. Started the car. CEL went out on it's own and fuse still ok.
4. Shut the car off and reconnected the air pump. Started the car, fuse still ok, CEL still off.
5. Drove to the grocery store and grabbed a few things, CEL off, came home, CEL off.
6. Shut off car and connected code reader. No codes now and fuse is still ok.

So what do you make of all that?

If it stays like this, then you just saved me a ton of headache and probably $100+ in dealership diags. I don't want to get my hopes up though.

Sincere thanks Jon316G.

 

Did you notice anything weird with the relay (harness slightly unplugged, moisture buildup, etc)?

 

No moisture and the connection seemed ok.

 

When this first happened did you notice if the air pump stayed on continuously or did it shut off after a couple minutes?

 

I'm not really sure. I don't know what it's suppose to sound like. Until tonight the fuse has been blown since I got the car. After I reconnected the pump and started the car, I put my hand on the pump to feel for vibration but I could have been feeling the normal engine vibration through it.

Is the pump suppose to come on for every start? or just cold starts?

 

Just cold starts.
Only thing I can think of is the contacts in the relay may have gotten stuck and kept the circuit closed.
Even then, its hard to see why it would blow the fuse unless the pump got overloaded from being on continuously.
But that might even be stretching it.

 

About to leave for work. I'll let you know later whether the CEL stays off or not.

 

Ok, so the CEL came back on. However the fuse is still ok. Pulled P0410 code again.

 

I had the same code for the air pump. the air pump was replaced and the dealership refreshed the DTC. CEL wouldnt go off still, went back a few days later and they never looked at the fuse, so when the fuse blew the air pump still got power and burned the pump out. 750 dollars later it could of jsut been a fuse replaced. thought the dealership would be the best place to go to service my 04 rx8 mazda. guess not. My advice learn as much as you can about the RX8 so you dont get raped.

 

Right now, the CEL is on (P0410) and the fuse is good. So does this mean it has to be the pump or the relay? The dealership I bought the car from is going to pay for the part(s) because the light has been on since I picked up the car.

Thanks for the advice.

-Matt

 

Hard to say... P0410 is such a generic code for an air system problem.
It could be the control valve, solenoid valve, air pump relay, or the pump itself.
You would need to look at each one of these individually to narrow it down.
If the dealer is going to buy the part(s) why not just let them deal with it?

 

I guess I'll have to take it to a mazda dealer to get it diagnosed. The dealership I purchased from isn't a mazda dealer so I'll be handing the bill over to them once it's fixed.

 

Hi Malgeo,

Have you solve your fault 0410?

my car is also having this problem now... How did you or your dealer solve the 0410?

 

As long as the fuse doesn't blow your ok.
Only need air pump for emissions at cold start.
Don't need it on the car.
Need to replace for emission testing and registration.

 

I recently had this problem too and I need an emissions test soon. I put in a new fuse and then started the car cold with the air pump disconnected. Fuse is still good, so I'm guessing my air pump is shot. I'll take it apart this weekend to see what I can see. If the fuse would have still blown with the pump disconnected I'd say it would be more likely a problem with the relay.