QuestionUpdate to problem.
I must have tried that self diagnostic procedure a hundred times.
No matter what I do even when I make mistakes it will just give me a two second blink at the start and then 16 short blinks.
I have a manual but it has the diagnostic lights on the ECM and mine are on the dash. I also have located all wires going into and out of the AC brain.
If I feed 12 volts straight to the talk lock solenoid it works fine.
According to the manual this problem of talk lock dropping out after 30 seconds would occur if wire number 25 ( the engine speed wire ) was incorrect.
The manual says it should be 9/12 volt with ignition . Mine has no voltage at all.
So I am trying to locate where the voltage for this wire would originate from. I have tried a rev sensor that is located at the timing cover but this checks out to be producing an increasing voltage with engine revs just like the manual says.
I am now suspecting that the taco and the engine speed for the AT brain may work off something else as well and that that sensor under the timing cover is just a engine speed sensor for the EGR system.
Any ideas where the wire (25) that is supposed to be feeding 12 volt to the AT controller is supposed to be getting this voltage from .
The manual showers it connected to the ECM but the ECM must be getting its information from somewhere..
The other thing is that the manual mentions a limp-home mode where if something goes wrong the vehicle goes into limp-home mode it also says that the light would give an eight second warning that this mode is engaged. It could be that my 16 short blinks are an actually 8 second warning although it actually blinks for 10 secs. But the manual says that this would be turned off if you shut the ignition for 3 seconds but I get this warning all the time.
But it dose make one think if that has something to do with why the talk converter lock works again after you shut down the ignition.
Its like the talk converter lock will lock up every time the ignition has been shut down but it will only last for about 20 seconds.
The manual says if the talk converter drops out after 30 second look to this wire number (25) at the AT controller ... mine had no volatge but I dont know where it is supposed to be getting the voltage from..
AnswerCherie,
The engine speed wire is a feed from the vehicle speed sensor (VSS) at the transmission. Power is fed to it and it has a square wave that is generated and sent to the speedometer cluster. The signal originates from the ECM. But, not in the traditional sense. That is, the ECM usually grounds circuits to activate systems. Micro relays ground bigger relays to complete circuits. Sort of runs you nuts. It even gets better that the VSS is picked up by the computer, yes the same one that grounds it on the other end, at the speedometer head. SO, you might have a bad connection at the speedometer head, a bad VSS or a defective relay. You will have to get a test light and start working your way through this rats nest of wire and relays.
