# Did early 1986 stanza wagons have a diagnostic computer?



## alank2 (Dec 29, 2006)

Hi,

Did early 1986 stanza wagons have a diagnostic computer?

I don't see any switch or lights, just a silver box about 3" wide, 4" tall, and 1" thick where I would expect the computer to be found. It says AT on it which makes me think it is a computer for an automatic transmission model, but I could be wrong.

Is this true, or am I looking at the wrong thing?

Thanks,

Alan


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## alank2 (Dec 29, 2006)

Hi,

Ok, I found it:

1986 Stanza Wagon 2WD - COMPUTER ECU = UNDER THE DRIVER SEAT! 

Thanks,

Alan


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## alank2 (Dec 29, 2006)

Hi,

The computer doesn't show any issues at all. I went through this diag procedure I found:

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Originally Posted by de2r

I would suggest running your codes first before removing anything. Under your driver's seat there is a diagnostic computer. On the right there is a switch. Procedure is as follows:

1.) Make sure it is turned OFF. 
2.) Turn your key in the ignition to ON. 
3.) Make sure that the 2 inspection bulbs (1 red, 1 green) stay on - this is a bulb check. 
4.) Now turn the switch on the computer to ON. The bulbs will flash out the codes for you. Example: 1 red flash + 2 green flashes = Code 12. Air Flow Meter.

Codes:

12 = Air Flow Meter
13 = Water Temperature Sensor
21 = Ignition
22 = Fuel Pump
23 = Throttle Valve Switch
31 = Idle Control System
32 = Start Signal
41 = Air Temperature Sensor

44 = System is operating properly

When finished retrieving codes, disconnect negative cable on your battery for at least 15 seconds. Reconnect cable and turn switch on computer to OFF. 

Now you can pin-point any faults.
You're aware that when you run your codes the control unit cycles through the system and checks everything automatically. It then throws back Code 23, 31 and 32. You need to press your gas pedal and release. It will then flash Codes 31 and 32. Start your engine. It should then flash 31. Turn your headlights ON and then OFF. It should then flash Code 44 (which means all systems are good.) Have you tried resetting the control unit since fixing your problem? Turn the control unit OFF and unplug it (or disconnect the NEG cable on your battery for more than 15 seconds.


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