HAIMA 7 - Troubleshooting Procedure

Troubleshooting
U-28
Troubleshooting procedure
Step Inspection Action
1 Inspect coolant temperature
l Is coolant warmed up sufficiently?
Yes Go to next step.
No Warm up engine to normal operation
temperature, then go to step 21.
*2
Verify whether malfunction is in air mix
actuator (+5v signal) system or elsewhere.
l Turn ignition switch to on position.
l Measure the voltage at terminal c (+5v
signal) of air mix actuator.
l Is voltage approximately equivalent to
+5v?
Yes Go to step 6.
No Go to next step.
*3
Inspect air mix actuator for continuity.
l Disconnect air mix actuator connector
l Measure the voltage at terminal c (+5v
signal) of air mix actuator
l Is voltage approximately equivalent to 5v?
Yes Inspect air mix actuator, then go to step
21.
No Go to next step.
*4
Inspect continuity of wiring harness between
rear climate control unit and air mix
actuator.
l Turn ignition switch to lock position.
l Disconnect rear climate control connector.
l Is there continuity between terminal c (+5v
signal) of air mix actuator conduct and
terminal h of rear climate control unit?
Yes Go to next step.
No Repair wiring harness between rear
climate control unit and air mix actuator,
go to step 21.
*5
Verify whether malfunction is in wiring
harness (short circuit to ground between rear
climate control unit and air mix actuator) or
in rear climate control unit.
l Is there continuity between terminal c (+5v
signal) of air mix actuator and ground?
Yes Repair wiring harness between rear
climate control unit and air mix actuator,
go to step 21.
No Replace rear climate control unit, go to
step 21.
*6
Inspect continuity of wiring harness between
rear climate control unit and air mix
actuator.
l Turn ignition switch to lock position.
l Disconnect connectors of rear climate
control unit from air mix actuator.
l Is there continuity between terminal f of
rear climate control unit and terminal e of
air mix actuator?
Yes Go to next step.
No Repair wiring harness between rear
climate control unit and air mix actuator,
go to step 21.
*7
Inspect wiring harness between rear climate
Yes Repair wiring harness between rear