TROUBLESHOOTING GUIDE — Symptoms: Insufficient cooling / No cooling / Intermittent cooling.

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IMPORTANT

Symptom: Insufficient cooling. No cooling. Intermittent cooling.

1
Checking refrigerant charge: 1. Run the engine at a fast idle. 2. Operate the air conditioner at maximum cooling for a few minutes. 3. Observe the sight glass to determine the amount of refrigerant and the related action as shown below.
05U0UX-020
2
Checking refrigerant pressure: 1. Connect the A/C manifold gauge set. 2. Operate the engine at 2,000 rpm and set the air conditioner to maximum cooling. 3. Measure the refrigerant pressure. 4. If the pressures are not as specified, refer to the chart on the next page and check the system.
05U0UX-021

Item	Symptom	Amount of refrigerant	Action
1	Bubbles present in sight glass	Insufficient refrigerant	Check refrigerant pressure, go to Step 2
2	No bubbles present in sight glass	Too much or proper amount of refrigerant	Turn air conditioner OFF, and watch bubbles (Refer to Items 3 and 4)
3	Immediately after air conditioner turned off, refrigerant in sight glass stays clear	Too much refrigerant	Check refrigerant pressure, go to Step 2
4	When air conditioner turned OFF, refrigerant foams, and then sight glass becomes clear	Proper amount of refrigerant	Refrigerant amount normal

SymptomBubbles present in sight glass

Amount of refrigerantInsufficient refrigerant

ActionCheck refrigerant pressure, go to Step 2

SymptomNo bubbles present in sight glass

Amount of refrigerantToo much or proper amount of refrigerant

ActionTurn air conditioner OFF, and watch bubbles (Refer to Items 3 and 4)

SymptomImmediately after air conditioner turned off, refrigerant in sight glass stays clear

Amount of refrigerantToo much refrigerant

ActionCheck refrigerant pressure, go to Step 2

SymptomWhen air conditioner turned OFF, refrigerant foams, and then sight glass becomes clear

Amount of refrigerantProper amount of refrigerant

ActionRefrigerant amount normal

Specification	Value
Normal pressure — Low-pressure sideRefrigerant pressure at 2,000 rpm, max cooling	147—294 kPa (1.5—3.0 kg/cm², 21—43 psi)kPa / kg/cm² / psi
Normal pressure — High-pressure sideRefrigerant pressure at 2,000 rpm, max cooling	1,177—1,619 kPa (12.0—16.5 kg/cm², 171—235 psi)kPa / kg/cm² / psi

Normal pressure — Low-pressure sideRefrigerant pressure at 2,000 rpm, max cooling

147—294 kPa (1.5—3.0 kg/cm², 21—43 psi)kPa / kg/cm² / psi

Normal pressure — High-pressure sideRefrigerant pressure at 2,000 rpm, max cooling

1,177—1,619 kPa (12.0—16.5 kg/cm², 171—235 psi)kPa / kg/cm² / psi

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