ol"blue

No, I believe it's supposed to go into the back of the ac/heater control that sits in the dash, below the radio. When you move the dash control **** to "Vent", or Defrost", that's what makes it move the doors.

rookcherokee

My control unit only has a wire harness connected to it. No vacuum lines anywhere, not even a spot for them. I'll take a pic.

rookcherokee

ol"blue

The vacuum circuits where the black line from the firewall goes in, is shown in the pic in post # 5 in this thread posted yesterday. http://www.jeepsunlimited.com/forums....php?p=4740095

ol"blue

There's 5 lines there. The black one at 12 o'clock of the 5 is the vacuum line from the firewall. Or where it should go if missing.

rookcherokee

I know, I just can't seem to find where this is actually located:


Behind my control unit is just that wiring harness seen in the picture I took. Everywhere I read says the vacuum lines should be behind there as well

ol"blue

My '97 ZJ FSM diagram of the ac/heater control panel shows a vacuum harness on it. Don't know where it's located on the '95.

rookcherokee

Ahh, I was afraid of that. Thanks for all your help so far Blue!

Anyone have the diagram for the '95 ac/heat control panel?

rookcherokee

I got a FSM for the '95 Grand Cherokee and it doesn't have a diagram for it at all. I'm stumped

Any ideas?

rookcherokee

Does anyone know if the "Automatic Temperate Control System" runs off of vacuum or electric? That's what I have in mine, and the guy in this thread says the two run differently.

http://www.jeepforum.com/forum/f13/n.../#post13253535

Could this be why I don't have a vacuum line at the "t" going to the firewall? And no vacuum harness behind the control panel?

seb4130ny

I purchased a new a/c hose and everything was fine but when I charged the system, the line blew off from the high side coupler. How do I reattach that line correctly using the coupler? I insert the hose in but the coupler doesn't click or anything and I can actually pull it out by hand (have to pull hard). Am I missing something here? Thanks.

ol"blue

I went to a couple of places today to check into this. The Automatic Temperature Control system is electrically controlled, not vacuum controlled. So I looked at the pic of your ac control, and it has two large ***** with the dial temp setting, not three large *****. So you have the ATC system.
This is from my '97 ZJ FSM. It may be different in your '95 manual. The system can run a self diagnostic.

ATC SYSTEM
The Automatic Temperature Control (ATC) controller
has a system self-diagnostic mode. The controller
is capable of troubleshooting each of its input and
output circuits. When the controller detects a fault
and places it in memory, an “Er” is momentarily displayed
in the heater-A/C control panel vacuum fluorescent
display area, but it will only be displayed
once during each ignition cycle. The ATC controller is
capable of three different types of self-diagnostic
tests, as follows:
² Fault Code Tests
² Input Circuit Tests
² Output Circuit/Actuator Tests
The information that follows describes how to read
the self-diagnostic display, how to enter the ATC controller
self-diagnostic test mode, how to select the
three self-diagnostic test types, and how to perform
the three different tests.
SELF-DIAGNOSTIC DISPLAY
In the self-diagnostic mode, the test information is
displayed in the vacuum fluorescent display area of
the heater-A/C control. The area of the display where
the temperature control comfort level is normally displayed
is called the Test Selector. The Test Selector is
used to display fault codes, identify the test mode,
and show the values of the circuits being tested. The
following information describes how the values in the
Test Selector display should be interpreted.
(1) The Select Test mode will have only 00 displayed
in the Test Selector, and no stick man will be
displayed. This is the self-diagnostic mode from
which the various tests may be selected.
(2) If the stick man floor arrow (bottom) is showing,
the displayed Test Selector value will be a range
of numbers below zero (Fig. 13).
(3) If the stick man appears, but no arrows are
showing, the displayed Test Selector value will be a
range of numbers between zero and ninety-nine (Fig.
14).(4) If the stick man panel arrow (middle) is showing,
the displayed Test Selector value will be a range
of numbers between 100 and 199 (Fig. 15).
(5) If the stick man panel (middle) and defrost
(top) arrows are showing, the displayed Test Selector
value will be a range of numbers between 200 and
255 (Fig. 16).
(6) t any time during the self-diagnostic tests, you
may return to the Select Test mode by turning the temperature
rotary control one click in either direction.
Again, the stick man and arrows are not shown in the
Select Test mode. At this point, you have the option of
monitoring or testing another circuit (Fig. 17).
ENTERING THE ATC SELF-DIAGNOSTIC MODE
To enter the ATC self-diagnostic mode, perform the
following:
(1) Depress the A/C and Recirc buttons at the
same time and hold. Rotate the rotary temperature
control **** clockwise one click.
(2) If you continue to hold the A/C and Recirc buttons
depressed, you will see all of the display segments
illuminate. If a segment fails to illuminate,
the vacuum fluorescent display is faulty.
(3) After viewing the segment test, release the A/C
and Recirc buttons. This will put the Test Selector
value at 00, and no stick man will be displayed. This
is the Select Test mode. At this point a number of
tests can be selected, however, the Fault Code Test
should be performed first.

FAULT CODE TESTS
Fault codes are two-digit numbers that identify a
circuit that is malfunctioning. There are two different
kinds of fault codes.
1. Current Fault Codes - Current means the
fault is present right now. There are two types of current
faults: input faults, and system faults.
2. Historical Fault Codes - Historical or stored
means the fault occurred previously, but is OK right now.
A majority of historical fault codes are caused by intermittent
wire harness or wire harness connector problems.
NOTE: A battery disconnect will erase all faults stored
in Read Available Memory (RAM). It is recommended
that all faults be recorded before they are erased.

RETRIEVING FAULT CODES
(1) To begin the Fault Code Tests you must be in
the Select Test mode. With 00 displayed in the Test
Selector and no stick man, push either the A/C or
Recirc button.
(2) The stick man will appear indicating you have
entered the Fault Code Tests. The values displayed
in the Test Selector will range from 00 to 64.
(3) Fault codes will appear and repeat if there are
more than one. Record all of the fault codes, then see
the Current and Historical Fault Code charts for the
descriptions. If there are no fault codes, the display
value remains at 00.
(4) If a Fault Code 25 or 29 is displayed, the ATC
control module must be replaced before any further
testing is performed.
(5) For more detailed information about a fault
code, see the Input Circuit Tests or the Output Circuit/
Actuator Tests.

Fail Code/Description Circuit Description
00 = No Faults
01 = Circuit open In-Vehicle Temperature Sensor
02 = Circuit open Solar Sensor Input Circuit
03 = Circuit open Front Panel Blower/Fan Control Input
04 = Circuit open Front Panel Mode Control Input
05 = Circuit open Blend Air Door Feedback Circuit
06 = Circuit open Mode Door Feedback Circuit
07 = Feedback too high Blower/Fan Feedback Circuit
08 = Circuit shorted In-Vehicle Temperature Sensor
09 = Circuit shorted Solar Sensor Input Circuit
10 = Circuit shorted Front Panel Blower/Fan Control Input
11 = Circuit shorted Front Panel Mode Control Input
12 = Circuit shorted Blend Air Door Feedback Circuit
13 = Circuit shorted Mode Door Feedback Circuit
14 = Feedback too low Blower/Fan Feedback Circuit
15 = Door not responding Mode Door Feedback Circuit
16 = Door not responding Blend Air Door Actuator Drive Circuit
17 = Door travel range too small Mode Door Feedback Circuit
18 = Door travel range too large Mode Door Feedback Circuit
19 = Door travel range too small Blend Air Door Actuator Drive Circuit
20 = Door travel range too large Blend Air Door Actuator Drive Circuit
21 = Calibration data error Calibration and CPU Data
22 = BCM message missing Collision Detection C2D Bus Inputs
23 = PCM message Missing Collision Detection C2D Bus Inputs
24 = CPU error Calibration and CPU Data
25 = Reserved
26 = Reserved
27 = Reserved
Current Fault Codes

24 - 18 HEATING AND AIR CONDITIONING ZG
DIAGNOSIS AND TESTING (Continued)
Fail Code/Description Circuit Description
28 = Circuit was open In-Vehicle Temperature Sensor
29 = Circuit was open Solar Sensor Input Circuit
30 = Circuit was open Front Panel Blower/Fan Control Input
31 = Circuit was open Front Panel Mode Control Input
32 = Circuit was open Blend Air Door Feedback Circuit
33 = Circuit was open Mode Door Feedback Circuit
34 = Feedback was too high Blower/Fan Feedback Circuit
35 = Circuit was shorted In-Vehicle Temperature Sensor
36 = Circuit was shorted Solar Sensor Input Circuit
37 = Circuit was shorted Front Panel Blower/Fan Control Input
38 = Circuit was shorted Front Panel Mode Control Input
39 = Circuit was shorted Blend Air Door Feedback Circuit
40 = Circuit was shorted Mode Door Feedback Circuit
41 = Feedback was too low Blower/Fan Feedback Circuit
42 = Door was not responding Mode Door Feedback Circuit
43 = Door was not responding Blend Air Door Actuator Drive Circuit
44 = Door travel range was too small Mode Door Feedback Circuit
45 = Door travel range was too large Mode Door Feedback Circuit
46 = Door travel range was too small Blend Air Door Actuator Drive Circuit
47 = Door travel range was too large Blend Air Door Actuator Drive Circuit
48 = Calibration data was in error Calibration and CPU Data
49 = BCM message was missing Collision Detection C2D Bus Inputs
50 = PCM message was Missing Collision Detection C2D Bus Inputs
51 = CPU was in error Calibration and CPU Data
52 = Reserved
53 = Reserved
54 = Reserved
Historical Fault Codes

CLEARING FAULT CODES
Current faults are cleared whenever the problem
goes away. To clear a historical fault, depress and
hold either the A/C or Recirc button for at least three
seconds. The faults have been cleared when two horizontal
bars appear in the display.

INPUT CIRCUIT TESTS
In the Input Circuit Test mode, the status of input
circuits can be viewed and monitored. If a failure
occurs within an input circuit the controller will display
a “?” for unknown values, “OC” for an open circuit,
or “SC” for a short circuit.
(1) To begin the Input Circuit Tests you must be in
the Select Test mode.
(2) With 00 displayed in the Test Selector and no
stick man, turn the rotary temperature control ****
until the test number you are looking for appears in
the Test Selector display. See the Circuit Testing
charts for a listing of the test numbers, test items,
test types, system tested, and displayed values.
(3) To see the circuit input values, depress the A/C
or Recirc button. The values displayed will represent
the input seen by the ATC controller.

OUTPUT CIRCUIT/ACTUATOR TESTS
In the Output Circuit/Actuator Test mode, the output
circuits can be viewed, monitored, overridden,
and tested. If a failure occurs in an output circuit,
test the circuit by overriding the system. Test the
actuator through its full range of operation. When
the override control has been activated, the display
will be flashing. The Test Selector will display feedback
information about the output circuit being
tested.
(1) To begin the Output Circuit/Actuator Tests you
must be in the Select Test mode.
(2) With 00 displayed in the Test Selector and no
stick man, turn the rotary temperature control ****
until the test number you are looking for appears in
the Test Selector display. See the Circuit Testing
charts for a listing of the test numbers, test items,
test types, system tested, and displayed values.
(3) To see the output value, depress the A/C or
Recirc button. The values displayed will represent
the output from the ATC controller.
(4) To enter the actuator test, depress the A/C or
Recirc button. The display will blink, indicating you
are in the actuator test mode. Manual tests are those
in which you will have to depress and hold the A/C or
Recirc button to control the output. Automatic tests
are those in which you will have to depress the A/C
or Recirc button once to generate the output.

Test
No.
Test
Item
Test
Type
System
Tested
Displayed
Values
01 Blower Control Switch
(A/D)
I Blower System 9?” 9OC” 9SC” 00-255
02 Blower Feedback I Blower System 9?” 00-255
03 Blower Speed O/A Blower System 00-255
04 Hi Blower Relay O/A Blower System 00=OFF 01 = ON
05 Mode Control A/D I Mode Door System 9OC” 9SC” 00-255
06 Mode Door Feedback I Mode Door System 9OC” 9SC” 00-255
07 Panel Stop I Mode Door System 9?” 00-255
If “?” is displayed, activate Mode 11 to
find panel stop position.
08 Defrost Stop I Mode Door System 9?” 00-255
If “?” is displayed, activate Mode 11 to
find defrost stop position.
09 A/C Request O/A A/C System 00 = OFF 01 = ON
10 Mode Door Position O/A Mode Door System 00-255
It is possible to command the door
position beyond the stops.
The motor will try to move there.
11 Mode Motor O/A Mode Door System Pressing A/C or RECIRC button for 3
sec. begins reinitalization.
00 = searching for panel stop
01 = searching for defrost stop
02 = moving toward panel
03 = moving toward defrost
04 = in position
05 = stalled moving toward panel
06 = stalled moving toward defrost
07 = feedback error
12 Mode Motor Drive
Lines
O Mode Door System 00 = stopped (lines low)
01 = toward defrost
02 = toward panel
03 = stopped (lines high)
13 Recirc Door O/A Recirc Door System 00 = continuous operation (lines
grounded)
01 = fresh
02 = recirc.
03 = stopped (lines open)
14 In-Vehicle Temp. A/D I Temperature Inputs 9OC” 9SC” 00-255
15 Blend Door Feedback I Blend Door System 9OC” 9SC” 00-255
16 Blend Door Cold Stop I Blend Door System 9?” 00-255
17 Blend Door Hot Stop I Blend Door System 9?” 00-255

18 In-Vehicle Temperature I Temperature Inputs 9OC” 9SC” -40 to +60 C
(-40 to + 140 F)
19 Ambient Sensor I CCD -40 to + 60 C
(-40 to +140 F)
20 Solar Sensor A/D I Sun Intensity Input 9OC” 9SC” 00-255
21 Engine Coolant I CCD 9?” -40 to + 185 C
(-40 to +260 F)
22 Vehicle Speed
(MPH/KPM)
I CCD 9?” 00-255
23 Engine RPM (x100) I CCD 00-82
24 Blend Door Motor O/A Blend Door System Pressing A/C or RECIRC button for 3
sec. begins reinitialization.
00 = searching for hot stop
01 = searching for cold stop
02 = moving to warmer
03 = moving to cooler
04 = in position
05 = stalled moving to warmer
06 = stalled moving to cooler
07 = feedback error
25 Blend Door Motor O/A Blend Door System 00-255
It is possible to command the door
position beyond the stops. The motor
will try to move there.
26 Blend Door Motor
Lines
O/A Blend Door System 00 = stopped (lines low)
01 = toward cold
02 = toward hot
03 = stopped (lines high)
27 Lights On I Headlight Switch 00 = OFF 01 = ON
28 Dimming I PWD System 9?” 00-255
29 Dimming Level O/A Dimming System 9?” 00-255
30 ROM & EEPROM 00 = FF
31 ROM & EEPROM 00 = FF
32 ROM & EEPROM 00 = FF
33 ROM & EEPROM 00 = FF
34 ROM & EEPROM 00 = FF
35 ROM & EEPROM 00 = FF
36 ROM & EEPROM 00 = FF
37 ROM & EEPROM 00 = FF

ol"blue

Might be the wrong hose?

stev-o

my ac is only coming out of the defrost up by the windshield and not out of the vents why is that it use to work just fine

rookcherokee

Thanks for that Blue. Going to be putting the dash together partially today and run the diagnostic to see if it's throwing any of these codes.