Operation CHARM: Car repair manuals for everyone.
Home >> Lexus >> 2009 >> SC 430 V8-4.3L (3UZ-FE) >> Repair and Diagnosis >> Heating and Air Conditioning >> Testing and Inspection >> Component Tests and General Diagnostics >> Air Conditioning System >> Back-Up Power Source Circuit
Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

(Some people have issue connecting. LEMON is investigating. For now, use Firefox or change your DNS server)

Or, hide this message: temporarily or permanently

Back-Up Power Source Circuit








AIR CONDITIONING: AIR CONDITIONING SYSTEM: Back-up Power Source Circuit

Back-up Power Source Circuit

DESCRIPTION

This circuit supplies a back-up power source for the A/C amplifier. Power is supplied even if the ignition switch is OFF and is used for diagnostic trouble code memory, etc.

WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

1. INSPECT FUSE (A/C)
(a) Remove the A/C fuse from the passenger side junction block.
(b) Measure the resistance of the fuse.
Standard resistance:
Below 1 Ohms
NG -- REPLACE FUSE
OK -- Continue to next step.
2. CHECK WIRE HARNESS (A/C AMPLIFIER - BATTERY)




(a) Disconnect the A10 amplifier connector.
(b) Measure the voltage of the wire harness side connector.
Standard voltage:






NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE
pro multis · About Operation CHARM