Toyota Sienna Service Manual: Heater relay (for rear air conditioning system)
ON-VEHICLE INSPECTION
1. INSPECT REAR HEATER RELAY
(a) Remove the rear heater relay.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance 
If the resistance is not as specified, replace the rear heater relay.
Heater relay
ON-VEHICLE INSPECTION
1. INSPECT HEATER RELAY
(a) Remove the heater relay.
(b) Measure the resistance according to the value(s) in
the table below.
Standard resistance
If the resistance i ...
Air conditioning control assembly
COMPONENTS
...
Other materials:
How to proceed with
troubleshooting
1 VEHICLE BROUGHT TO WORKSHOP
2 CUSTOMER PROBLEM ANALYSIS
3 CHECK AND CLEAR DTCs
Refer to the diagnostic check/clear
4 PROBLEM SYMPTOM CONFIRMATION
5 SYMPTOM SIMULATION
6 CHECK DTC
7 CHECK IF THE SAME SYMPTOM APPEARS IN THE NAVIGATION SYSTEM
Refer to the navigation system
8 PROBLE ...
Removal
1. REMOVE INSTRUMENT PANEL SUB-ASSEMBLY WITH PASSENGER AIRBAG ASSEMBLY
HINT:
Refer to the instructions for removal of the instrument
panel sub-assembly w/ passenger airbag assembly (See
page IP-5).
2. REMOVE HEATER TO FOOT DUCT NO.1
(a) Remove the clip and the heater to foot duct No. 1.
3 ...
Intake Air Temperature Sensor Gradient Too High
DESCRIPTION
The Intake Air Temperature (IAT) sensor, mounted on the Mass Air Flow (MAF)
meter, monitors the IAT.
The IAT sensor has a built-in thermistor with a resistance that varies according
to the temperature of the
intake air. When the IAT becomes low, the resistance of the the ...
