HAIMA 7 - Page 452

Troubleshooting
U-42
Step Inspection Action
*25
Inspect continuity of wiring harness between
fuse block and a/c relay (at switch side).
l Turn ignition switch to on position.
l Measure voltage at a/c relay connector
terminal d (a/c control signal).
l Is voltage approximately equivalent to b+
(positive battery voltage)?
Yes Go to next step.
No Repair wiring harness between fuse
block and a/c relay, go to step 28.
*26
Inspect a/c relay (at switch side)
l Inspect a/c relay.
l Is it normal?
Yes Install a/c relay, go to next step
No Replace a/c relay, go to step 28.
*27
Verify whether malfunction is in
electromagnetic clutch or wiring harness
(continuity between a/c relay and
electromagnetic clutch).
l Measure voltage at electromagnetic clutch
connector terminal a (a/c control signal).
l Is voltage approximately equivalent to b+
(positive battery voltage)?
Yes Inspect electromagnetic clutch, and then
go to next step.
No Repair wiring harness between a/c relay
and electromagnetic clutch, go to next
step.
*28 Verify whether malfunction symptom occurs
after repair.
l Does cold air blow out (if the result of
performance test of refrigeration system is
normal.)?
Yes Troubleshooting completed. Explain
causes to customer.
No Recheck malfunction symptoms, and
then repeat from step 1 if malfunction
reoccurs.
Xii. Noise with operation of a/c system
12
Noise with operation of a/c system
Malfunction
symptom
Noise from a/c compressor hose of electromagnetic clutch or refrigerant pipeline
Possible causes
Electromagnetic clutch operation noise. Step 3
l A/c compressor operation noise. Steps 4-8
l A/c compressor sliding noise. Steps 9-11
l Hose or refrigerant pipeline interference noise. Steps 12