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ATC questions.

Are the little orange lights on the ATC supposed to flash all the time?  They come on solid when you turn it on but start to flash shortly there after.  The system seems to function fine, heat and A/C work fine.

I did the test on it and it returns an 88, so I dunno.
One 88

ATC questions.

Reply #1 –
nope,,

my DIY link write up says 88 is a pass.  Ill have to look up why you have an 88 and flashing lights. 

first thing i would do is unhook the pos or neg battery cable for the night and see if it resets.  I recall something like that for intermittant faults.

how'd you get so many darn green boxes?

ATC questions.

Reply #2 –
Just tested it after I warmed the car up and got a code 02.  Gona try and sort that out tomorrow. 

Oh and I emptied my pm box.
One 88

ATC questions.

Reply #3 –
That used to happen to my old '88 T-Bird Sport. Seemed like in the fall and spring, the ATC unit went haywire exactly like what you're describing. But in the summer and winter it worked nearly perfectly. One of the codes I used to get all the time was the 02-Blend door actuator fault. Never did figure out if the actuator had a dead spot, or if the self-test on the ATC head unit just threw that code. I also changed the in-cab temp sensor with no improvement. It's a good thing that car had a moonroof and two working power window motors, that's all I can say.

You could try changing the ATC head unit and blend door actuator, see if that helps.

ATC questions.

Reply #4 –
E-man....  Per your website code 02 is not the blend door but the floor/panel actuator.
One 88

ATC questions.

Reply #5 –
Maybe it was the 01 code that I got then. I had always suspected the actuator but it seemed to work perfectly when all the lights on the ATC head unit didn't flash. That led me to believe it was a faulty ATC head. Never got the chance to change it out, as I sold the car.

ATC questions.

Reply #6 –
Thats the thing I don't get.  Everything works fine.  The air comes out of the defrost, panel or floor depending on what you select.
One 88

ATC questions.

Reply #7 –
try this stuff out................
This exact code happened to someone last year i would estimate because i did a write up on it.  I would also assume the thread is searchable but i cant remember who had the problem. I would

I think i have an eatc link in my diy link that will take you directly to the thread where i posted the wiring diagrams as well.
check that you if you can.

here is how my diy link works,
there is an index and then when you find your topic, you have to scroll down to the item.  Since the eatc is in the upper most of the index, that tells me that i put up that info within the past 6 months. 


==============================================
EATC or ATC codes and troubleshooting

ATC Codes
possible of codes 1-15, code 88 is system passes test

Code trouble code 2 displayed
**assume first off that your Floor Panel is jammed with debris from buildup ect which may prevent the door from moving freely and cause this code.
**we are going to bypass the EATC system in the following steps
1 Disconnect the two identical 14 pin conn's at rear of ATC
2 Turn Ign switch to Run
J1= (or conn C124) pass side control assembly, pin 11 should be blank, pin 1 should be BR/LG
J2= (or conn C126) driver side control assembly, pin 12 should be blank, pin 1 should be LB/RD

**verify you have a good ground on J2 pin 4 via continuity check from vehicle chassis to the conn.

3 Supply yourself with two jumper wires and perfrom the two tests.
*caution, you are going to supply Direct battery voltage to the Floor panel via pin J2-8 to test that it moves. Make sure you have power on this pin. The door should move when the J2-4 is made which is ground.

4 jumper J1-6(pink) to J2-8(+bat LB/Pk AND J1-9(wh/y) to J2-4(bk)
*******The book says to do this test quickly, as in no more than one second or you may burn something up.
If door swings fully in one direction the proceed to next step by reversing the polarity to swing door in opposite direction

5 jumper J1-9 to J2-8 AND J1-6 to J2-4.
if door swings opposite driection fully, proceed on.

Resistance check of Floor Panel sensor **J1 only***
the sensor is nothing more than a variable resistor with three legs.
Pin 4 is one side of the resistor, pin 5 is the other side of the resistor, pin 13 is the moving center tap.

6 total resistance of sensor at J1 pins 4 to 5 should be about 500-600ohms

7 This step is kinda tricky and really depends on which position your door is in at this moment in time, especially if there is debris in the duct work that prevents the door from moving fully.
anyway, resistance from J1 pins 13(R/lg) to 4(BK/W) should be 70-550ohms
Resistance from J1 pins 13(R/lg) to 5(LG/O) should be 200-500 ohms.

8 Here is what i would do if you can manually move the door with your hand or something. Treat this sensor like it were a throttle position sensor.
from J1 pins 13 to 5 with an ohm meter, measure resistance and manually move the door slowly watching the resistance scale increase and decrease smoothly.

from J1 pins 13 to 4 with an ohm meter, measure resistance and manually move the door slowly watching the resistance scale increase and decrease smoothly.

ATC questions.

Reply #8 –
Some wiring info

ATC questions.

Reply #10 –
check electrical tech for threads posted in may/07.  thats when i first updated my diy link to include info like this.

ATC questions.

Reply #11 –
today this happened to me.  Up here in DC there was a pretty decent ice storm and i had the car running while i ran back up to the room to gather my stuff.

I hit the rear defrost button and the mother started flashing.  Im like,, heyyyyy.

So i chip away ice and shut off the rear defrost.  Shut off car and restart,,,, Problem went away. 

Im wondering if you have the rear defrost on and the led is burnt out. 

just checking and sharing what happened to me.

ATC questions.

Reply #12 –
Nope rear defrost works and the light works too.

Its been working fine other than the car loosing water and the heat going cold due to a too low fluid level.
One 88

ATC questions.

Reply #13 –
do you have one of those water temp sensors up near the heater core hoses? Mine is just laying off to the side and my atc works fine so that cant be it i wouldnt think.

ATC questions.

Reply #14 –
That sensor is in the heater hose and working fine I guess.  The sytem only blows when hot water is present.  I've got a couple of these head units so I think I'll swap it out.  Problem is one is an hour away and the other is three hours away.
One 88