Inspection Procedure

1. Disconnect the connectors from the clearance warning ECU C9 and air conditioner amplifier connector A10 or A11.
2. Measure the resistance according to the value(s) in the table below.

   Standard resistance 

   TESTER CONNECTION AND SPECIFIED CONDITION
   
   

   Tester Connection	Condition	Specified Condition
   +B - SK	Always	Below 1 Ω
   +B - Body ground	Always	10 kΩ or higher

Fig 1: Checking Harness And Connector (Clearance Warning ECU - Air Conditioner Amplifier)
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK: Go to Next Step 

1. Measure the resistance according to the value(s) in the table below.

   Standard resistance 

   TESTER CONNECTION AND SPECIFIED CONDITION
   
   

   Tester Connection	Condition	Specified Condition
   E - Body ground	Always	Below 1 Ω

Fig 2: Checking Harness And Connector (Clearance Warning ECU - Body Ground)
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK: Go to Next Step 

1. Disconnect the clearance warning ECU connector.
2. Turn the ignition switch ON.
3. Turn the clearance sonar main switch ON.
4. Measure the voltage between terminals +B and E of the ECU.

   Standard voltage: 10 to 14 V 

   Result 

   RESULT REFERENCE
   
   

   Result	Proceed to
   OK	A
   NG	B (Auto A/C)
   NG	C (Manual A/C)

Fig 3: Inspecting Clearance Warning ECU
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

B: Go to step 4 

C:  Go to step  5

A: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE 

1. Check that the malfunction disappears when a known good printed wire integration board sub-assembly is installed.

   OK: Malfunction disappears. 

NG: REPLACE AIR CONDITIONER AMPLIFIER 

OK: REPLACE PRINTED WIRE INTEGRATION BOARD SUB-ASSEMBLY 

1. Check that the malfunction disappears when a known good integration panel sub-assembly is installed.

   OK: Malfunction disappears. 

NG: REPLACE AIR CONDITIONER AMPLIFIER 

OK: REPLACE INTEGRATION PANEL SUB-ASSEMBLY