CCOT Air Conditioning (A/C) System Diagnosis. Buick Riviera 1998

For 1990-2009 cars only

Makes 🢒 Buick 🢒 1998 🢒 Riviera 🢒 HVAC 🢒 HVAC Systems - Automatic 🢒 CCOT Air Conditioning (A/C) System Diagnosis

The primary purpose of these charts is to diagnose problems in the following areas:

•	The mechanical portion of the refrigeration system

•	The mechanical portion of the heating system

•	The air delivery portion of the air conditioning system

Before using the charts, refer to Functional Check in order to verify that the control portion of the air conditioning system is functioning properly.

Step	Action	Value(s)	Yes	No
1	Verify that the ambient temperature is at least the specified value. Start the engine. Allow the engine to reach normal operating temperature. Select the AUTO mode. Set the temperature control to the MAX COLD position. Turn the blower control to the HIGH position. Does the blower operate?	5°C (41°F)	Go to Step 2	Go to HVAC Blower Controls Circuit Description
2	Does the A/C compressor operate?	--	Go to Step 3	Go to HVAC Compressor Clutch Does Not Engage
3	Is the A/C system cooling insufficient?	--	Go to Cooling Insufficient - Air Conditioning (A/C) Inoperative	Go to Step 4
4	Is the A/C system heating insufficient?	--	Go to Heating Insufficient	Go to Step 5
5	Is the A/C system temperature control improper?	--	Go to HVAC Temperature Controls Circuit Description	Go to Step 6
6	Is the A/C system blower speed improper?	--	Go to HVAC Blower Controls Circuit Description	Go to Step 7
7	Is the A/C system noisy?	--	Go to Noise Diagnosis	Go to Step 8
8	Does air flow from the wrong outlets?	--	Go to Functional Check	Go to Step 9
9	Does the A/C produce an odor?	--	Go to Odor Diagnosis	Go to Step 10
10	Are all of the diagnoses complete?	--	System OK	--