The DPF indicator on my 2009 Mazda3 2.0 D Sport started flashing.

At first I thought this was serious, but it transpired it was just the service interval indicator needed reseting.

I had changed the oil and filter on schedule, but had been unable to find reference to resetting the service interval, and some 1000 - to 2000 miles later the "DPF" started flashing.

Some research on the net re-assured me it was just the service interval, BUT, I could find no way of resetting it without a Mazda specific computer ( Can not be done with an ODBII reader as it isn't a "Fault" ). I could see the sevice interval on my ELM327 based service tool but couldn't reset it.

There are a couple of Web pages on the net re: resetting Mazda 6, and Mazda 5 cars, and by amalgamating the info from these, plus some guess work, I eventually managed to reset the service counter.

DISCLAIMER :- This is what I did, and it worked for me. You get what you pay for, and this information is free ! I am not responsible for you wrecking you car because your not an authorised Mazda Technician !

Here's how I did it :-

IMPORTANT: If the DPF light is up, but solid, it does NOT need this proceedure, it needs the DPF regenerating, and if that doesn't work, the DPF replacing ( or deleting ? !)

1) Locate the 6 pin service commector under the bonnet. It is just behind the bonnet catch, on the loom that passes from left to right along the top of the radiator.

2) With a length of wire / cable ( approx 2 metres) connect pin "E" - the top right one, when the locking tang receptical is on top- to a good earth ( I use a pair of locking grip pliers on the battery negative terminal)

3) Get in the drivers seat and close all doors ( including the tailgate). This is the "step" that caught me out !

4) Do not start the engine, but switch on the dash using the key.

5) Pump the accelerator pedal quite quickly, over it's full range, ten times.

6) The glow heater symbol should start flashing as well. If not switch off ingnition and repeat from step 4, with a different cadance on the accelerator pedal

7) Wait 20 seconds, and switch off.

8) Remove the earth wire, and every thing should be back to normal