Diagnosis Pin on ECU

[Whitetal]

I have a check engine light. I use my palm to check it. I have a serial comm error. My car has been sitting for a year now. Before the diagnosis port worked before with my palm. I check for pulse with voltimeter. Not getting signal. Anyone know if I can check the code strait from the ecu pin? Also could I just hook up my palm strait to the ecu since the diagnosis port isn't working?

 

[Whitetal]

Is it pin 1 which on the vfaq it says it's the Self-Diagnosis Output or pin 2 which is the Diagnosis/Data transfer select terminal? Should I splice into those wires?

 

[luv2rallye]

http://www.troublecodes.net/mitsu/

 

[Whitetal]

That link tells me what I already know. I already know how to retrieve the code from the diagnostic port and I know the codes already. What's wrong is that there is no pulse coming from the port so I want to know if I can get the code strait from the ecu and I need to know which pins it is?

 

[luv2rallye]

Well pin 1 on the diag connector comes straight from ECU pin 1 so unless the wire between them is broken you will read the same thing there. If so, your ECU diag port isn't working.
http://www.vfaq.com/mods/ecu-harness-1G.html

 

[steve]

Does the car run?
Perhaps the ECU is in need of some TLC.

 

[Whitetal]

Thanks. That's what I needed to know. I didn't know that pin 1 from the diagnostic port goes strait to pin 1 on the ecu. That is very helpful to know. I'll try it from there.

The car runs but very crappy. What do you mean by tlc?

 

[steve]

There are three pins/wires as part of the 1G datalogging interface. Pin 1 on both the DLC and ECU is the data line. It swings between ground and battery voltage.

Pin 10 on the DLC connects to pin 2 on the ECU and is the mode select line. Grounding this pin puts the ECU into various diagnostic modes including datalogging mode.

The last is pin 12 on the DLC. It's the common ground for both the datalogger interface and the ECU.

Steve