akrx7

Where can one get a self diagnonis checker that the factory service manual talks about???

Templeswain

I think you make one. Its like reading morse code only with lights, I think.

Maybe the loudroom knows.

RotaryExperimental

you should just have to jump 2 conections (not sure which ones manuel should say) the turn the key to the on position and watch the check engine light and count the flashes.

Some one correct me if im wrong please

J-Rat

iTrader: (2)

FOr the 1987 RX-7, you run the motor, and you use to LEDs to scan codes. No jumpering necessary.

I think the link is in the FAQs at the top of this page.

J-Rat

iTrader: (2)

http://2ndgenrx7.freeservers.com/

da_cain

I happend to already have a tester light made that I use for my TPS, and after adjusting my TPS I still have existing problems so I moved on to doing a self diagnostic. I Put my positive wires into the ABR terminal of the self diagnostic connector, and the others in their respective spots, turned car on, and turned my key to On position, and none of my LED's lit up at all, and on the website it says that they will both come on for about 3 seconds upon key goin to ON position. I got no 3 seconds of LED nor any codes out of them, any ideas to why?

HAILERS

Make sure the ABR has 12v on it. It should be a black/white wire.

If it does, then take your led's and put one lead on the positve post of the battery and the other on the negative post. The light should light up.

If it does, that indicates to me that the ECU is the culprit. You might onm out each of those two wires to the ECU for continuity to make sure the wires are good. If they are good.....the ECU is inoperative in that area for unknown reasons.

The tester can be had from Mazdatrix, but its a waste of money especially if you know the leds won't light up when put in the proper places on the green connector.

da_cain

I tested ABR current by hooking up positive to ABR connector and negetive to battery and light came on. But the DCC1 and 2 I get nothing from at anytime. Still think it could be a problem with the ECU?

WAYNE88N/A

Remember, our ECU circuit is ***-backwards- DCC 1 and 2 should both have +12vdc on them (to ground), but the lights should be OFF (because the ECU hasn't grounded 'em yet).

With the pos meter lead in either 1 or 2, and the neg lead to chassis ground, turning the key on should produce zero voltage for about 3 seconds (if using lights, the light would be on for three seconds). Both DCC 1 and 2 should exhibit this, which means that the ECU self-check is good. If you don't get the above, then look at the ECU as being the culprit...

da_cain

So, I gave what you said a try, I put my positive side into DCC1 and grounded off the other side to battery, turned key on, no lights came on, tried the same for DCC2. If this a sign that my ECU is bad that would explain a few ghosts I have been chasing down in my car. Is there a way I can test MY ECU with a DMM? KNow the REsistances I should be getting from it by chance, Im gonna hit the manual up now to see if I can find some inspection notes for it.


** found the control unit on my online manual, and it is telling me I need an Engine Signal Monitor that hooks right up inbetween ECU and the Wiring harness into it.

HAILERS

ABR is a source of 12vdc.

DCC 1 and 2 are pulsed grounds from the ECU.

It's likely that the only thing wrong with the ECU are these two outputs.

You don't need a signal monitor. All you need is a meter and access to the ECU's three plugs plus the manual section that says CONTROL UNIT and lists what the input/output of each wire is with the engine idling or just the key to ON.

We now know your lights work. Good. We also know the ECU's output on those two wires are kaput. Blame it on the previous owner.

da_cain

OK yeah IC, Ive got tables stating what voltages each slot should have, it says I need to check after car has warmed up, could you clear this up for me......do I shut off the motor and unplug the harness to test it?

HAILERS

I suppose Wayne's description of how the ABBR etc works is correct and I am wrong in the above.

To test the outputs/inputs of the ECU at the ECU you leave the plugs connected to the ECU and backprobe the wires in the plug.