Suzuki 2000 Grand Vitara SQ625 Service Manual page 238

TABLE B-4 A/C SIGNAL CIRCUIT CHECK (IF EQUIPPED)
CIRCUIT DIAGRAM
TERMINAL ARRANGEMENT OF ECM (PCM) COUPLER VIEWED FROM HARNESS SIDE
CIRCUIT DESCRIPTION
ECM (PCM) outputs A/C ON signal (one of the signals for A/C control module to control the A/C) to A/C control
module when A/C switch signal inputted to ECM (PCM) and engine conditions are specified.
INSPECTION
STEP
1 A/C Switch Signal Circuit check:
(1) Remove ECM (PCM) cover.
(2) Check voltage between E61-28 and ground under
following conditions.
Ignition switch ON and A/C switch and/or heater
blower switch OFF 10 – 14 V
Ignition switch ON and both A/C switch and heater
blower switch ON 0 – 1.5 V
Are check results as specified?
ACTION
ENGINE (H25 ENGINE) 6-1-127
1. A / C control module
YES
Go to Step 2.
NO
Faulty "Y/B" wire,
evaporative
temperature is
bellow 1_C or faulty
A/C system.