How to Check for DTCs With the HDS
Note. There are three methods used to check for DTCs. The recommended method is to use the Honda Diagnostic System (HDS) with the appropriate software, plugged into the data link connector (DLC). The second method is to run the self-diagnostic function built into the climate control unit. The third method is to use the B-CAN system diagnosis test mode A (see TROUBLESHOOTING - B-CAN SYSTEM DIAGNOSIS TEST MODE A ).
Scheme 397
- Make sure the ignition switch is in LOCK (0).
- Connect the HDS to the DLC (A) located under the driver's side of the dashboard.
- Turn the ignition switch to ON (II).
- Make sure the HDS communicates with the vehicle and the climate control unit. If it does not, go to the DLC circuit troubleshooting (see «DLC CIRCUIT TROUBLESHOOTING»(ref-512893-S17266721462012110400000) ).
- Select HVAC/CLIMATE CONTROL in the BODY ELECTRICAL menu.
- Select DTCs in the HVAC/CLIMATE CONTROL menu.
- Check for DTCs. If any DTCs are indicated, write down the DTCs, then go to the indicated «DTC TROUBLESHOOTING»(ref-512960-S14107420772012110500000) . If no DTCs are indicated, refer to «SYMPTOM TROUBLESHOOTING»(ref-512960-S13219826422012110500000) . NOTE: After troubleshooting, clear the DTCs with the HDS. For specific operations, refer to the user's manual that came with the HDS.
Checking for DTCs
The temperature display indicates single or multiple DTCs. If no DTCs are present, the indicator remains blank.
Note. If the driver's temperature indicator segments A, C, D, E, G, J, K, and the AUTO indicator or the A/CON indicator are on at the same time, there may be an open in the climate control unit ground circuit.
Scheme 398
| DTC (Driver's Temperature Indicator Segments, AUTO, and A/C ON Indicator) | Detection Item |
|---|---|
| A and AUTO | An open in the in-car temperature sensor circuit (see DTC B1225 OR DTC INDICATOR A AND AUTO: AN OPEN IN THE IN-CAR TEMPERATURE SENSOR CIRCUIT ) |
| B and AUTO | A short in the in-car temperature sensor circuit (see DTC B1226 OR DTC INDICATOR B AND AUTO: A SHORT IN THE IN-CAR TEMPERATURE SENSOR CIRCUIT ) |
| C and AUTO | An open in the outside air temperature sensor circuit (see DTC B1227 OR DTC INDICATOR C AND AUTO: AN OPEN IN THE OUTSIDE AIR TEMPERATURE SENSOR CIRCUIT ) |
| D and AUTO | A short in the outside air temperature sensor circuit (see DTC B1228 OR DTC INDICATOR D AND AUTO: A SHORT IN THE OUTSIDE AIR TEMPERATURE SENSOR CIRCUIT ) |
| E and AUTO | An open in the sunlight sensor circuit (see DTC B1229 OR DTC INDICATOR E AND AUTO: AN OPEN IN THE SUNLIGHT SENSOR CIRCUIT ) |
| F and AUTO | A short in the sunlight sensor circuit (see DTC B1230 OR DTC INDICATOR F AND AUTO: A SHORT IN THE SUNLIGHT SENSOR CIRCUIT ) |
| G and AUTO | An open in the evaporator temperature sensor circuit (see DTC B1231 OR DTC INDICATOR G AND AUTO: AN OPEN IN THE EVAPORATOR TEMPERATURE SENSOR CIRCUIT ) |
| H and AUTO | A short in the evaporator temperature sensor circuit (see DTC B1232 OR DTC INDICATOR H AND AUTO: A SHORT IN THE EVAPORATOR TEMPERATURE SENSOR CIRCUIT ) |
| J and AUTO | An open in the humidity sensor circuit (see DTC B2967 OR DTC INDICATOR J AND AUTO: AN OPEN IN THE HUMIDITY SENSOR CIRCUIT ) |
| K and AUTO | A short in the humidity sensor circuit (see DTC B2968 OR DTC INDICATOR K AND AUTO: A SHORT IN THE HUMIDITY SENSOR CIRCUIT ) |
| A and A/C ON | An open in the air mix control motor circuit (driver's) (see DTC B1233 OR DTC INDICATOR A AND A/C ON: AN OPEN IN THE AIR MIX CONTROL MOTOR CIRCUIT (DRIVER'S) ) |
| B and A/C ON | A short in the air mix control motor circuit (driver's) (see DTC B1234 OR DTC INDICATOR B AND A/C ON: A SHORT IN THE AIR MIX CONTROL MOTOR CIRCUIT (DRIVER'S) ) |
| C and A/C ON | A problem in the air mix control motor circuit, linkage, door, or motor (driver's) (see DTC B1235 OR DTC INDICATOR C AND A/C ON: A PROBLEM IN THE AIR MIX CONTROL MOTOR CIRCUIT, LINKAGE, DOOR, OR MOTOR (DRIVER'S) ) |
| D and A/C ON | An open in the passenger's air mix control motor circuit (see DTC B1236 OR DTC INDICATOR D AND A/C ON: AN OPEN IN THE PASSENGER'S AIR MIX CONTROL MOTOR CIRCUIT ) |
| E and A/C ON | A short in the passenger's air mix control motor circuit (see DTC B1237 OR DTC INDICATOR E AND A/C ON: A SHORT IN THE PASSENGER'S AIR MIX CONTROL MOTOR CIRCUIT ) |
| F and A/C ON | A problem in the passenger's air mix motor circuit, control linkage, door, or motor (see DTC B1238 OR DTC INDICATOR F AND A/C ON: A PROBLEM IN THE PASSENGER'S AIR MIX CONTROL MOTOR CIRCUIT, LINKAGE, DOOR, OR MOTOR ) |
| G and A/C ON | An open in the mode control motor circuit (see DTC B121A OR DTC INDICATOR G AND A/C ON: AN OPEN IN THE MODE CONTROL MOTOR CIRCUIT ) |
| H and A/C ON | A short in the mode control motor circuit (see DTC B121B OR DTC INDICATOR H AND A/C ON: A SHORT IN THE MODE CONTROL MOTOR CIRCUIT ) |
| J and A/C ON | A problem in the mode control motor circuit, linkage, door, or motor (see DTC B1240 OR INDICATOR J AND A/C ON: A PROBLEM IN THE MODE CONTROL MOTOR CIRCUIT, LINKAGE, DOOR, OR MOTOR ) |
| K and A/C ON | An open in the recirculation control motor circuit (see DTC B2986 OR DTC INDICATOR K AND A/C ON: AN OPEN IN THE RECIRCULATION CONTROL MOTOR CIRCUIT ) |
| L and A/C ON | A short in the recirculation control motor circuit (see ) |
| M and A/C ON | A problem in the recirculation control motor circuit, linkage, door, or motor (see DTC B2983 OR DTC INDICATOR M AND A/C ON: A PROBLEM IN THE RECIRCULATION CONTROL MOTOR CIRCUIT, LINKAGE, DOOR, OR MOTOR ) |
| N and A/C ON | A problem in the blower motor circuit (see DTC B1241 OR DTC INDICATOR N AND A/C ON: A PROBLEM IN THE BLOWER MOTOR CIRCUIT ) |
| A | Climate control unit internal error (see DTC INDICATOR A: CLIMATE CONTROL UNIT INTERNAL ERROR ) |
| B | Output shaft (countershaft) speed sensor signal error. Check for DTCs in the A/T system, and go to the indicated DTC'S TROUBLESHOOTING . If no DTCs are found, replace the climate control unit; with navigation (see CLIMATE CONTROL UNIT REMOVAL/INSTALLATION ), without navigation (see WITHOUT NAVIGATION ) |
| C | Engine coolant temperature (ECT) sensor signal error. Check for DTCs in the PGM-FI system, and go to the indicated DTC'S TROUBLESHOOTING . If no DTCs are found, replace the climate control unit; with navigation (see CLIMATE CONTROL UNIT REMOVAL/INSTALLATION ), without navigation (see WITHOUT NAVIGATION ) |
| D | Communication bus line error (BUS-OFF) (see DTC U1280: COMMUNICATION BUS LINE ERROR (BUS-OFF) ) |
Displaying Sensor Inputs at the Climate Control Unit
The climate control unit has a mode that displays sensor inputs it receives. This mode shows you what the climate control unit is receiving from each of the sensors, one at a time, and it can help you determine if a sensor is faulty.
Checks Before Using the Sensor Input Display Mode
- Turn the ignition switch to ON (II), and check the recirculation door function; press the RECIRCULATION button to switch from FRESH to RECIRC. The air volume and sound should change slightly.
- Set the driver's climate control switch to the desired test temperature: Press the AUTO button on, the LED turns on. Press the SYNC button off, the LED turns off. When selecting the test temperature, note these items: "Lo" temperature setting will default to MAX COOL, VENT, and RECIRC(A/C ON) or FRESH (A/C OFF). "Hi" temperature setting will default to MAX HOT, HEAT, or HEAT/DEF (switches between HEAT, HEAT/DEF according to the outside air temperature sensor reading), and FRESH. 58 through 86°F (14 through 30°C) settings will use the automatic climate control logic.
- Turn the ignition switch to LOCK (0).
Run the Sensor Input Display Mode
- Turn the ignition switch to LOCK (0).
- Press and hold both the AUTO and the RECIRCULATION buttons, then start the engine.
- After the engine starts, release both buttons. The audio-HVAC subdisplay (with navigation) or the audio-HVAC display (without navigation) will flash the sensor number and then the value for that sensor. Record the value displayed.
- To advance to the next sensor, press the REAR WINDOW DEFOGGER/MIRROR DEFOGGER button. NOTE: The sensor values will be displayed in degrees Celsius (°C) or an alphanumeric code. Use the chart to convert the value to degrees Fahrenheit (°F). If the sensor value displays "Er", this indicates there is an open or short in the circuit or sensor. Check for DTCs using the HDS, or use the climate control self-diagnostic function. If necessary, compare the sensor input display to a known-good vehicle under the same test conditions. If the sensor displayed value is out of the normal range, refer to the sensor test or substitute a known-good sensor, and recheck. Sensor Item Displayed Value 1 Mode positioning % 2 In-car temperature °C 3 Outside air temperature °C 4 Solar radiation sensor value: dark = 00, flashlight = 04, cloudy = 10, sunny = 65 10 kcal/m 2 -h 5 Evaporator outlet air temperature °C 6 Driver's air mix opening (low value indicates cooler air distribution, higher value indicates warmer air distribution) % of opening 7 Passenger's air mix opening (low value indicates cooler air distribution, higher value indicates warmer air distribution) % of opening 8 Recirculation control opening % of opening 9 Vehicle speed (vehicle must be driven to display speed) 10 km/h A Engine coolant temperature °C b Vent temperature air out (TAO) °C C Humidity sensor value %rh CELSIUS TO FAHRENHEIT CONVERSION TABLE °C °F 0 32 1 34 2 36 3 37 4 39 5 41 6 43 7 45 8 46 9 48 10 50 11 52 12 54 13 55 14 57 15 59 16 61 17 63 18 64 19 66 20 68 21 70 22 72 23 73 24 75 25 77 26 79 27 81 28 82 29 84 30 86 31 88 32 90 33 91 34 93 35 95 36 97 37 99 38 100 39 102 40 104 41 106 42 108 43 109 44 111 45 113 46 115 47 117 48 118 49 120 50 122 51 124 52 126 53 127 54 129 55 131 56 133 57 135 58 136 59 138 60 140 61 142 62 144 63 145 64 147 65 149 66 151 67 153 68 154 69 156 70 158 71 160 72 162 73 163 74 165 75 167 76 169 77 170 78 172 79 174 80 176 81 178 82 180 83 181 84 183 85 185 86 187 87 189 88 190 89 192 90 194 91 196 92 198 93 199 94 201 95 203 96 205 97 207 98 208 99 210 ALPHANUMERIC CONVERSION TABLE Display Reading (Alphanumeric) °C °F % A1 thru A9 - 1 thru -9 30 thru 16 - 1 thru -9 B0 thru B9 -10 thru -19 14 thru -2 - 10 thru -19 C0 thru C9 -20 thru -29 -4 thru -20 -20 thru -29 D0 thru D9 -30 thru -39 -22 thru -38 -30 thru -39 E0 thru E9 -40 thru -49 -40 thru -56 -40 thru -49 F0 thru F9 -50 thru -59 -58 thru -74 +100 thru +109 ALPHANUMERIC CONVERSION TABLE MODE POSITIONING) Display Reading (Alphanumeric) Mode Position 0 VENT 18 HEAT/VENT-1 33 HEAT/VENT-2 50 HEAT 66 HEAT/DEF-1 80 HEAT/DEF-2 F0 DEF
- To cancel the sensor input display mode, press the AUTO button or turn the ignition switch to LOCK (0).
Humidity/In-Car Temperature Sensor
The humidity sensor consists of two sensors. One sensor is for humidity detection, and the other is for in-car temperature detection. When the climate control unit receives signals about the in-car condition from the humidity sensor, and judges that the humidity in the vehicle is very low, the climate control unit reduces the A/C compressor runtime. Engine power loss is kept to a minimum, and fuel economy is increased.
Scheme 399
Humidity/In-Car Temperature Sensor Quality
The capacitance of the humidity sensor changes by the adsorption and the evaporation of moisture. The resistance change of the humidity sensor changes the output voltage.
Scheme 400
A/C Pressure Sensor
The A/C pressure sensor converts A/C pressure into electrical signals to the PCM.
| A/C System Pressure | Sensor Output Voltage (V out) | System Operation |
|---|---|---|
| Abnormally low pressure: Below 196 kPa (2.00 kgf/cm 2 , 28.4 psi) | Below 0.685 V | The PCM disengages the A/C compressor clutch. The radiator and the A/C condenser fans operate based on engine coolant temperature. |
| Normal operating pressure: Above 196 kPa (2.00 kgf/cm 2 , 28.4 psi) Below 1, 500 kPa (15.30 kgf/cm 2 , 217.6 psi) | 0.686 V to 2.409 V | The PCM cycles the A/C compressor clutch based on cooling demand. The radiator and the A/C condenser fans operate at low speed unless the engine coolant temperature exceeds 206 °F (97°C). |
| High operating pressure: Above 1, 500 kPa (15.30 kgf/cm 2 , 217.6 psi) Below 3, 138 kPa (32.00 kgf/cm 2 , 455.1 psi) | 2.409 V to 4.575 V | The PCM cycles the A/C compressor clutch based on cooling demand. The radiator and the A/C condenser fans operate at high speed. |
| Abnormally high pressure: More than 3, 138 kPa (32.00 kgf/cm 2 , 455.1 psi) | Above 4.575 V | The PCM disengages the A/C compressor clutch. The radiator and the A/C condenser fans operate based on engine coolant temperature. |
The response of the A/C pressure sensor is shown in the graph.
Note. When the refrigerant is below 196 kPa (2.00 kgf/cm 2 , 28.4 psi) or above 3, 138 kPa (32.00 kgf/cm 2 , 455.1 psi), the PCM turns the A/C compressor clutch relay off to protect the A/C compressor. When the refrigerant pressure is above 1, 500 kPa (15.30 kgf/cm 2 , 217.6 psi), the PCM switches the radiator and the A/C condenser fans to high speed.
Scheme 401
Scheme 402
Scheme 403
Scheme 404
The i-Dual zone climate control system automatically controls the temperature and the air direction to the driver and passenger's side depending on the angle of the sun and the direction of the vehicle. It calculates information such as date, time, longitude, and latitude from the navigation system, as well as the radiant strength of the sun from the sunlight sensor, to determine the appropriate mode position and temperature to be directed to each side.
Scheme 405
In the event that the navigation system malfunctions, or when driving in areas where the navigation system cannot determine the vehicle position (non-coverage areas, tunnels, etc.), the climate control system will operate the same as a vehicle without navigation.
Scheme 406
| Cavity | Wire color | Terminal name | Description | Signal |
|---|---|---|---|---|
| 1 | GRY | AMD-P-Dr | Detects potentiometer signal of driver's air mix control motor (door position) | With ignition switch ON (II): about 0.5-4.5 V (depending on driver's air mix control motor position) |
| 2 | LT BLU (1) YEL (2) | AMD-P-As | Detects potentiometer signal of passenger's air mix control motor (door position) | With ignition switch ON (II): about 1.5-4.5 V (depending on passenger's air mix control motor position) |
| 3 | BLU (1) PNK (2) | RFD-P | Detects potentiometer signal of recirculation control motor (door position) | With ignition switch ON (II): about 1.0-4.0 V (depending on recirculation control motor position) |
| 4 | RED (1) LT GRN (2) | MDD-P | Detects potentiometer signal of mode control motor (door position) | With ignition switch ON (II): about 0.5-4.5 V (depending on mode control motor position) |
| 5 | Not used | Not used | ||
| 6 | RED (1) LT GRN (2) | IG2 | IG2 power source | With ignition switch ON (II): battery voltage |
| 7 | GRY (1) GRN (2) | M-DEF | Outputs to drive mode control motor to DEF side | With ignition switch ON (II) and mode control motor moving to DEF: battery voltage |
| 8 | YEL (1) WHT (2) | M-VENT | Outputs to drive mode control motor to VENT side | With ignition switch ON (II) and mode control motor moving to VENT: battery voltage |
| 9 | PNK | M-HOT-Dr | Output to drive driver's air mix control motor to HOT side | With ignition switch ON (II) and driver's air mix control motor moving to HOT: battery voltage |
| 10 | PUR (1) ORN (2) | M-REC | Output to drive recirculation control motor to RECIRCULATE side | With ignition switch ON (II) and recirculation control motor moving to RECIRCU: battery voltage |
| 11 | LT BLU | M-COOL-Dr | Output to drive driver's air mix control motor to COOL side | With ignition switch ON (II) and driver's air mix control motor moving to COOL: battery voltage |
| 12 | RED (1) PUR (2) | M-FRS | Output to drive recirculation control motor to FRESH side | With ignition switch ON (II) and recirculation control motor moving to FRESH: battery voltage |
| 13 | BRN (1) WHT (2) | M-COOL-As | Output to drive passenger's air mix control motor to COOL side | With ignition switch ON (II) and passenger's air mix control motor moving to COOL: battery voltage |
| 14 | LT GRN | M-HOT-As | Output to drive passenger's air mix control motor to HOT side | With ignition switch ON (II) and passenger's air mix control motor moving to HOT: battery voltage |
| 15 (1) | GRN v | BUS-DATA | Communication signal to driver's climate control switch | With ignition switch ON (II): pulses |
| 16 | Not used | Not used | ||
| 17 | BLK (1) LT BLU (2) | Tr | Detects in-car temperature sensor signal | With ignition switch ON (II): about 1.0-4.0 V (depending on in-car temperature) |
| 18 | YEL (1) PUR (2) | Tsun | Detects sunlight sensor signal | With ignition switch ON (II) and no sunlight or sensor covered up: 3.56 V With ignition switch ON (II) and sunlight on sensor: less than 3.56 V (depending on sunlight intensity) |
| 19 | LT GRN (1) BLU (2) | Tam | Detects outside air temperature sensor signal | With ignition switch ON (II): about 1.0-4.0 V (depending on outside air temperature) |
| 20 | BRN | Teva | Detects evaporator temperature sensor signal | With ignition switch ON (II): about 1.0-4.0 V (depending on evaporator temperature) |
| 21 | Not used | Not used | ||
| 22 | PUR | ACS | Outputs A/C on/off signal | With ignition switch ON (II), normal A/C pressure, and A/C switch ON: less than 0.2 V With ignition switch ON (II), normal A/C pressure, and A/C switch OFF: battery voltage |
| 23 | BLU (1) PUR (2) | AC-SI | Communication signal to subdisplay potentiometer signal | With ignition switch ON (II): pulses |
| 24 | LT BLU (1) RED (2) | AC-CLK | Communication signal from subdisplay | With ignition switch ON (II): pulses |
| 25 (2) | GRY | ILL+ | Inputs voltage for illumination | With combination light switch ON: battery voltage |
| 26 | Not used | Not used | ||
| 27 (2) | RED | ILL - (BULB) | Detects illumination control signal | With illumination switch ON: changed voltage (depending on dashlights brightness controller) |
| 28 | Not used | Not used | ||
| (1) With navigation (2) Without navigation | ||||
| (1) | With navigation |
| (2) | Without navigation |
Scheme 407
| Cavity | Wire color | Terminal name | Description | Signal |
|---|---|---|---|---|
| 1 | BLU | BLW-V | Feedback signal of power transistor drain voltage | With ignition switch ON (II): about 0 V - battery voltage (depending on blower motor speed) |
| 2 | PUR (1) YEL (2) | BLW-G | Outputs power transistor gate voltage | With ignition switch ON (II) and fan control button OFF: less than 0.2 V With ignition switch ON (II) and fan control button ON: about 4.0 V - battery voltage (depending on blower motor control) |
| 3 | Not used | Not used | ||
| 4 | BLK | GND | Ground for climate control unit (G502) | Less than 0.2 V at all times |
| 5 | RED (1) BLU (2) | B-CAN L | B-CAN communication signal | With ignition switch ON (II): pulses |
| 6 | WHT (1) PNK (2) | B-CAN H | B-CAN communication signal | With ignition switch ON (II): pulses |
| 7 | BLK | S5V | Outputs sensor 5 V | With ignition switch ON (II): about 5.0 V |
| 8 | GRY | HUM | Detects humidity sensor signal | With ignition switch ON (II): about 1.0-4.0 V (depending on humidity) |
| 9 | WHT (1) RED (2) | SENS-COM | Sensor ground | Less than 0.2 V at all times |
| 10 (1) | RED | AC-CLK1 | Communication signal from navigation unit | With ignition switch ON (II); pulses |
| 11 (1) | LT GRN | AC-SI | Communication signal to navigation unit | With ignition switch ON (II): pulses |
| 12 (1) | BRN | AC-S01 | Communication signal from navigation unit | With ignition switch ON (II): pulses |
| (1) With navigation (2) Without navigation | ||||
| (1) | With navigation |
| (2) | Without navigation |
