I have been doing a lot of work on my Eunos 800m lately and cant seem to clear my codes.

No matter what I do I keep getting codes 11 12 14 & 15 using the good old test light and jumper wire on the diagnostic plug to read out codes.

I previously had more codes but have since fixed them after changing the supercharger and fixing a few cracked and stuffed vac line and T pieces.
Anyways..... im still stuck on my original codes that I had when I first bought the car. cant get rid of them or even clear them. not too sure whats going on.

11 Intake air temp sensor: tested the resistance of the air cleaner and charger output sensors, were within spec. have a new sensor in the rear intake manifold. havent tested the old one as yet. long story. all plugs have 4.5+ volts at the plugs. code wont clear.

12 TPS fixed at 20% open: I believe I have fixed this.
re adjusted to the TPS with a feeler guage as per the FSM
- closed thottle has continuity between terminal c& d
- open 0.19mm still has continuity between terminal c& d
- open 0.37mm no continuity between terminal c& d
back probed to test output voltage and is also within spec at close and open with no jumps of drops in voltage. but this code wont bloody clear
I know its fixed as the throttle response is a millions times better than before, MUCH less throttle input required to get the revs up. Aslo back probed the TPS and was well within spec as per the FSM. No idea why this wont clear

14 Barometric sensor: shouldn't really affect economy or performance that greatly in the real world at close to sea level. It should default to normal atmospheric pressure so no too worried about this one. The sensor is inside the ECU anyways. happy to leave this one be.

15: o2 sensor feedback cancelled. My car only has 2 3wire o2 sensors. not the 2 4wire and 2 3 wire like the FSM says. Anyways replaced them both with universal PEC 3 wire 02 sensors. sensors tested within spec. this should have fixed the code but nope this one wont clear either. In the FSM is says to clear the codes (using the SST some mazda electrical code reading unit), start the engine then run at 1500-2000 rpm for at least 3 mins to reactivate the 02 feedback. I reset the codes (I think, see below) and ran the car within the rpm range for about 5 mins. No good , tried it while running on the highyway a couple of times but still the code remains.

Reseting codes: the code reader guide says to disconnect the neg battery terminal and hold the brakes on for at least 10 secs. I have had no luck doing this... I have left the battery completely disconnected with a 2x4 pushing the brakes nearly all day. no matter what I do these remaining codes will not reset and I cannot get the 02 sensor going again.


I have tried a spare ecu (same part number) and got the exact same codes.
Anyone know whats going on here, why cant I reset my codes and y cant I get the 02 sensor going again? this is killing me.

the only thing i havent tested is continuity between the sensors signal wire and the ECU pin. This is a huge PITA. its hard enough getting the plugs in and out of the ecu let along back probing specific pins to test them.
i highly doubt there is a wiring issue anyways. everything else on the car is working perfect.

I have a feeling these are like "hard" codes that only clear using the scanner.
Anyone know a scanner that works using the mazda 17pin to ODB converter
Any ideas would be greatly appreciated .
Cheers