Heater Control Switch Circuit: Procedure

WARNING: This page is about a different car, the 2011 Toyota Corolla. However, it is still accessible from the selected car via links, so may be relevant.

INSPECT NO. 3 HEATER CONTROL

Measure the resistance.

Remove the No. 3 heater control.
Disconnect the connector from the No. 3 heater control.

Fig 1: Identifying E65 Connector Terminals
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

Standard Resistance

Tester Connection	Switch Condition	Specified Condition
E65-2 (B) - E65-3 (A/C)	A/C switch: LOCK	Below 1 Ω
E65-2 (B) - E65-3 (A/C)	A/C switch: FREE	10 kΩ or higher
E65-7 (B) - E65-8 (E)*1	Air mix control dial: MAX HOT position	Below 1 Ω
E65-7 (B) - E65-8 (E)*1	Air mix control dial: except MAX HOT position	10 kΩ or higher

*1: w/ PTC Heater Assembly

Check that the indicator light comes on.
1. Connect a positive (+) lead from the battery to terminal 3 and a negative (-) lead from the battery to terminal 4, and check that the indicator light comes on.
  OK
  
  The indicator light comes on.

Check that the illumination comes on.

Connect a positive (+) lead from the battery to terminal 5 and a negative (-) lead from the battery to terminal 6, and check that the illumination comes on.

The illumination comes on.

TEXT IN ILLUSTRATION

*A	w/ PTC Heater Assembly
*a	Component without harness connected (No. 3 Heater Control)

NG → See step 4

OK: Go to next step

CHECK HARNESS AND CONNECTOR (NO. 3 HEATER CONTROL - BATTERY)

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

Fig 2: Identifying E65 Connector B & B*A Terminals

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Standard Voltage

Tester Connection	Switch Condition	Specified Condition
E65-2 (B) - Body ground	Ignition switch ON	11 to 14 V
E65-2 (B) - Body ground	Ignition switch off	Below 1 V
E65-7 (B) - Body ground*1	Ignition switch ON	11 to 14 V
E65-7 (B) - Body ground*1	Ignition switch off	Below 1 V

*1: w/ PTC Heater Assembly

TEXT IN ILLUSTRATION

*A	w/ PTC Heater Assembly
*a	Front view of wire harness connector (to No. 3 Heater Control)

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR

OK: Go to next step

CHECK HARNESS AND CONNECTOR (NO. 3 HEATER CONTROL - A/C AMPLIFIER)

Disconnect the connector from the A/C amplifier.

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

Standard Resistance

Tester Connection	Condition	Specified Condition
E65-3 (A/C) - E62-15 (A/C)*2	Always	Below 1 Ω
E65-4 (AIND) - E62-16 (LED)*2	Always	Below 1 Ω
E65-8 (E) - E63-14 (HEAT)*1	Always	Below 1 Ω
E65-3 (A/C) - E111-27 (A/C)*3	Always	Below 1 Ω
E65-4 (AIND) - E111-28 (LED)*3	Always	Below 1 Ω
E65-3 (A/C) - Body ground	Always	10 kΩ or higher
E65-4 (AIND) - Body ground	Always	10 kΩ or higher
E65-8 (E) - Body ground *1	Always	10 kΩ or higher

*1: w/ PTC Heater Assembly
*2: except TMC Made 2AZ-FE
*3: for TMC Made and except TMC Made 2ZR-FE

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR

OK → See step 5

REPLACE NO. 3 HEATER CONTROL. Refer to DISASSEMBLY
PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE. Refer to PROBLEM SYMPTOMS TABLE