1991 B2600i 5sp
The check engine light is on. To get the codes, everywhere I have looked it says to ground out the green single connector which is located at the driver side grill and fender intersection. I don't have a single connector there. I have a green single connetor on the passenger side firewall by the wiper motor. When i groud this one out, nothing happens on the light. I have a single white connector on the drivers side by the power steering resevoir. Any thoughts out there??????

no offence but with check engine lights you shold rally take it to the dealer to have it "correctly" diagnosed...if you dont know what your doing you may damage the pcm.

I had the same problem.
The green wire you are looking for is situated on the passenger side. Use the jumper trick to see if any code appears. Even try to have the code read at a mecanic's. If you don't a result, you have the same situation I had last year. I found the solution on a forum on the Internet but I don't remember where. It had also the problem codes to identify the problem.

It seems that Mazda wanted to make sure that the truck came back to a dealer's every 100 000km (60 000 miles). The Check engine light would come on even if there was no problem. The solution is in unplugging a certain wire under the dash on the driver's side and replugging it to the wire next to it. You will have to switch wires every 100 000km.

Find that forum and it will explain where the wires are and how t fix the problem.

A word of caution, I checked the codes myself. When I got no workable answer, I had the check engine verified by two different mecanics. Both came back negative and one suggested to check the entire wiring, a 8 hours job.

I made a quick search and here are interesting pages:

http://library.motoralldata.com/techRef/WebHelp/Emission_Control_Service_Reminder_Indicator_Reset_ Procedure/Emissions_Cntrl_Srv_Reminder_IRP_mazda.html

http://www.avproecm.com/errorcodes.htm

Found the solution, tried it everything is OK. I'll tell you in 90 000 km if I'm 100% right.

Good luck

I been almost a year since this post...I hope they have it fixed by now.:)