Thermometer at center duct

WARNING: This page is about a different car, the 2007 Suzuki Grand Vitara and 2006 Suzuki Grand Vitara. However, it is still accessible from the selected car via links, so may be relevant.

A/C SYSTEM INSPECTION CHART - THERMOMETER AT CENTER DUCT

Condition	Possible Cause	Correction
Crossing point is higher than acceptable range ("E" area)	Insufficient or excessive charge of refrigerant	Check refrigerant pressure.
	Dirty or bent A/C evaporator fins	Clean or repair.
	Air leakage from cooling (heater) unit or air duct	Repair or replace.
	Malfunctioning, switch over function of damper in cooling (heater) unit	Repair or replace.
	Compressor malfunction	Check compressor.
Crossing point is lower than acceptable range ("F" area)	Insufficient air volume from center duct (Heater blower malfunction)	Check blower motor and fan.
Crossing point is lower than acceptable range ("F" area)	Compressor malfunction	Check compressor.

NOTE: If ambient temperature is approximately 30°C (86°F), it is possible to diagnose A/C system in detail referring to the following table.

A/C SYSTEM INSPECTION CHART

Condition			Possible Cause	Correction
Manifold Gauge	MPa (kg/cm² ) (psi)	Detail
Lo	Hi	Detail
0.28 - 0.39 (2.8 - 3.9) (40 - 55)	1.34 - 1.67 (13.4 - 16.7) (191 - 237)	Normal condition	-	-
Negative pressure	0.5 - 0.6 (5 - 6) (71.2 - 85.3)	The low pressure side reads a negative pressure, and the high pressure side reads an extremely low pressure. Presence of frost around tubing to and from receiver/dryer and expansion valve.	Dust particles or water droplets are either stuck or frozen inside expansion valve, preventing the refrigerant from flowing.	Clean expansion valve. Replace it if it cannot be cleaned. Replace desiccant. Evacuate the A/C system and recharge with fresh refrigerant.
Normal: 0.28 - 0.39 (2.8 - 3.9) (40 - 55) ↑ ↓ Abnormal: Negative pressure	Normal: 1.34 - 1.67 (13.4 - 16.7) (191 - 237) ↑ ↓ Abnormal: 0.7 - 1.0 (7 - 10) (100 - 142)	During A/C operation, the low pressure side sometimes indicates negative pressure, and sometimes normal pressure. Also high pressure side reading fluctuates between the abnormal and normal pressure.	Expansion valve is frozen due to moisture in the system, and temporarily shuts off the refrigeration cycle.	Replace expansion valve. Replace desiccant. Evacuate A/C system and recharge with fresh refrigerant.
0.05 - 0.15 (0.5 - 1.5) (4.2 - 21.3)	0.7 - 1.0 (7 - 10) (100 - 142)	Both low and high pressure sides indicate low readings. Output air is slightly cold.	Insufficient refrigerant in system. (Refrigerant leaking)	Using a gas leak detector, check for leaks and repair as necessary. Recharge refrigerant to a specified amount. If the pressure reading is almost 0 when the manifold gauges are attached, check for any leaks, repair them, and evacuate the system.
0.4 - 0.6 (4 - 6) (56.9 - 85.3)	0.7 - 1.0 (7 - 10) (100 - 142)	Pressure on low pressure side is high. Pressure on high pressure side is low. Both pressure becoming equal right after A/C is turned OFF.	Internal leak in compressor	Inspect compressor and repair or replace as necessary.
0.35 - 0.45 (3.5 - 4.5) (50 - 64)	2.0 - 2.5 (20 - 25) (285 - 355)	High pressure reading on both low and high pressure sides.	Overcharged A/C system. Faulty condenser cooling operation. Faulty radiator fan operation.	Adjust refrigerant to specified amount. Clean condenser. Inspect and repair radiator fan.
0.35 - 0.45 (3.5 - 4.5) (50 - 64)		High pressure reading on both low and high pressure sides. Low pressure side tubing is not cold when touched.	Presence of air in A/C system. (Improperly evacuated)	Replace desiccant. Inspect quantity of compressor oil and presence of contaminants in oil. Evacuate system and recharge with fresh refrigerant.
0.45 - 0.55 (4.5 - 5.5) (64 - 78)		High pressure reading on both low and high pressure sides. Large amount of frost or dew on the low pressure side tubing.	Faulty expansion valve. Refrigerant flow is not regulated properly.	Replace expansion valve.