Climate Control Diagnostics Sub-sections

D8-40 -- Memory Display Channel 7, Checking
This channel displays the control information to the A/C programmer.

• Segment 1 lights up or flashes
  Temperature regulating flap E moves in direction 2 "heating," see section D8-60.
• Segment 2 lights up
  Recirculation/fresh air flap A is in position 2 "recirculation mode."
• Segments 3 and 5 light up
  Regulating flap B (footwell/defrost outlet) is in position 1 "air from instrument panel outlets."
• Segment 4 lights up
  Heater valve D is in position 1 (closed).
• Segment 5 lights up (segment 3 does not)
  Regulating flap B (footwell/defrost outlet) is in position 2 "air from instument panel outlets and to regulating flap (footwell/deforst).
• Segment 6 lights up
  Regulating flap C (footwell/defrost) is in position 2 "air from footwell outlets."
• Segment 7 lights up or flashes
  Temperature regulating flap E moves in direction 1 "cooling," see section D8-60.
• Segment 8 lights up
  Compressor on.
• Segment 9 lights up
  Radiator cooling fan runs on 1st speed.

D8-50 -- Memory Display Channel 17, Checking

• Segment 1 (decimal) lights up
  Compressor on.
• Segment 2 lights up
  Compressor off. A/C refrigerant high-pressure switch open.
• Segement 3 lights up
  Compressor off. Outside temperature too low or operating mode set to ECON or OFF. Check outside temperature sensors.
• Segment 4 lights up
  Compressor off. Electrical system voltage less than 9.5V.
• Segment 5 lights up
  Compressor off. A/C refrigerant low-pressure switch open.
• Segment 6 lights up
  Compressor off. Kick-down switch closed. A/C compressor should switch back on after 12 seconds.
• Segment 7 lights up
  Compressor off. Electronic thermoswitch (multi-function temp. sensor) closed.

D8-60 -- Memory Display Channel 18, Checking

• Segment 1 lights up
  Compressor on.
• Segment 2 lights up
  Radiator cooling fan runs on 1st speed.
• Segment 3 lights up
  Idle speed increases (A/C on).

Temperature Regulating Flap

 Cooling Position

 Heating position

D8-240 & D8-310 Temperature Sensor Values

Outside Temp Sensors (channels 4 & 5) Actual Temp C (F) Channel Value Resistance (ohms) -10 (14) 188 5636 -8 (18) 183 5097 -6 (21) 177 4558 -4 (25) 171 4088 -2 (28) 165 3688 0 (32) 159 3288 2 (36) 153 2992 4 (39) 146 2697 6 (43) 140 2439 8 (46) 134 2216 10 (50) 127 1995 12 (54) 122 1826 14 (57) 116 1657 16 (61) 110 1508 18 (64) 104 1379 20 (68) 98 1250 22 (72) 93 1150 24 (75) 88 1050 26 (79) 83 961 28 (82) 78 883 30 (86) 73 805 32 (90) 69 744 34 (93) 65 683 36 (97) 61 628 38 (100) 57 580 40 (104) 54 532 42 (108) 50 493 44 (111) 47 455 46 (115) 44 421 48 (118) 42 390 50 (122) 39 360 52 (126) 37 335 54 (129) 34 311 56 (133) 32 289 58 (136) 30 269 60 (140) 28 249

Inside Temp Sensors (channels 2 & 3) Actual Temp C (F) Channel Value Resistance (ohms) 4 (39) 187 7699 6 (43) 182 6951 8 (46) 177 6308 10 (50) 171 5666 12 (54) 166 5178 14 (57) 160 4690 16 (61) 154 4259 18 (64) 148 3886 20 (68) 142 3513 22 (72) 137 3225 24 (75) 131 2938 26 (79) 125 2683 28 (82) 119 2460 30 (86) 113 2237 32 (90) 108 2062 34 (93) 103 1888 36 (97) 97 1732 38 (100) 92 1595 40 (104) 87 1459 42 (108) 83 1350 44 (111) 78 1242 46 (115) 74 1144 48 (118) 70 1058 50 (122) 65 972

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