Heating/Air Conditioning System Description Without Climate Control (With A/C: Without Climate Control)

Heating/Air Conditioning System Description Without Climate Control

The air conditioning system removes heat from the passenger compartment by circulating refrigerant through the system.

This vehicle uses HFC-134a (R-134a) refrigerant, which does not contain chlorofluorocarbons. Pay attention to the following service items:

Do not mix refrigerants CFC-12 (R-12) and HFC-134a (R-134a). They are not compatible.
Use only the recommended polyalkyleneglycol (PAG) refrigerant oil (SANDEN SP-10) designed for the R-134a A/C compressor. Intermixing the recommended (PAG) refrigerant oil with any other refrigerant oil will result in A/C compressor failure.
All A/C system parts (A/C compressor, discharge line, suction line, evaporator, A/C condenser, receiver/dryer, expansion valve, O-rings for joints) are designed for refrigerant R-134a. Do not exchange with R-12 parts.
Use a halogen gas leak detector designed for refrigerant R-134a.
R-12 and R-134a refrigerant servicing equipment are not interchangeable. Use only a recovery/recycling/charging station that is U.L.-listed and is certified to meet the requirements of SAE J2210 to service the R-134a air conditioning systems.
Always recover refrigerant R-134a with an approved recovery/recycling/charging station before disconnecting any A/C fitting.

Oil Separator

Oil emission from the A/C compressor to the A/C line is reduced by placing the oil separator in the A/C compressor. This results in a thinner oil film inside of the heat exchanger (A/C condenser and evaporator). Air conditioning efficiency is increased without sacrificing engine peformance.

A/C Pressure Sensor

The A/C pressure sensor converts A/C pressure into electrical signals to the ECM/PCM.

The response of the A/C pressure sensor is shown in the graph.

Heating/Air Conditioning Door Positions

HVAC Control Unit Inputs and Outputs

Cavity Wire color Signal
1 BLK AIR MIX POTENTIAL +5 V OUTPUT
2 BRN EVAPORATOR TEMPERATURE SENOR OUTPUT
3 ORN MODE 1 OUTPUT
4 LT GRN MODE 2 OUTPUT
5 PUR MODE 3 OUTPUT
6 BLU MODE 4 OUTPUT
7 BLU BLOWER FEEDBACK INPUT
8 YEL POWER TRANSISTOR CONTROL OUTPUT
9 ——— ——— ———
10 ——— ——— ———
11 BRN^*1 BLU^*2 A/C SIGNAL OUTPUT
12 RED ILLUMI (-) OUTPUT
13 RED SENSOR COMMON GROUND INPUT
14 WHT MODE VENT OUTPUT
15 GRN MODE DEF OUTPUT
16 ORN RECIRCULATE INPUT
17 PUR^*1 RED^*2 FRESH INPUT
18 GRY AIR MIX POTENTIAL OUTPUT
19 LT BLU AIR MIX COOL OUTPUT
20 PNK AIR MIX HOT OUTPUT
21 BLK GROUND (G504) OUTPUT
22 BRN^*1 GRY^*2 REAR WINDOW DEFOGGER RELAY INPUT
23 LT GRN^*1 PUR^*2 IG2 (Power) INPUT
24 GRY ILLUMI (+) INPUT

Cavity	Wire color	Signal
1	BLK	AIR MIX POTENTIAL +5 V	OUTPUT
2	BRN	EVAPORATOR TEMPERATURE SENOR	OUTPUT
3	ORN	MODE 1	OUTPUT
4	LT GRN	MODE 2	OUTPUT
5	PUR	MODE 3	OUTPUT
6	BLU	MODE 4	OUTPUT
7	BLU	BLOWER FEEDBACK	INPUT
8	YEL	POWER TRANSISTOR CONTROL	OUTPUT
9	———	———	———
10	———	———	———
11	BRN^1 BLU^2	A/C SIGNAL	OUTPUT
12	RED	ILLUMI (-)	OUTPUT
13	RED	SENSOR COMMON GROUND	INPUT
14	WHT	MODE VENT	OUTPUT
15	GRN	MODE DEF	OUTPUT
16	ORN	RECIRCULATE	INPUT
17	PUR^1 RED^2	FRESH	INPUT
18	GRY	AIR MIX POTENTIAL	OUTPUT
19	LT BLU	AIR MIX COOL	OUTPUT
20	PNK	AIR MIX HOT	OUTPUT
21	BLK	GROUND (G504)	OUTPUT
22	BRN^1 GRY^2	REAR WINDOW DEFOGGER RELAY	INPUT
23	LT GRN^1 PUR^2	IG2 (Power)	INPUT
24	GRY	ILLUMI (+)	INPUT

*1: LHD type
*2: RHD type