3.
Is the problem found?
 | ▶ Repair the trouble causing part and go to "Verification of Vehicle Repair". |
 | ▶ Go to "Power Circuit Inspection". |
Air-heater Relay which is controled by ECM supplies and cut electrical power to Air-heater. ECM activates or deactivates Air-heater Relay based on inputted signal such as Engine coolant temperature signal.
P0541 is set when '0A' is detected in Air-heater relay control circuit for more than 1 sec. This code is due to open or short to ground in Air-heater relay control circuit or internal open in relay component.
Item | Detecting Condition | Possible Cause | ||
DTC Strategy | ● Voltage monitoring | ● Air-heater relay circuit ● Air-heater component | ||
Enable Conditions | ● IG KEY "ON" | |||
Threshold Value | ● Short to GND, Wiring open | |||
Diagnostic Time | ● 1.0 sec. | |||
Fail Safe | Fuel Cut | NO | ● - | |
EGR Off | NO | |||
Fuel Limit | NO | |||
MIL | NO | |||
Electrical systems consist of a lot of harness and connectors, poor connection of terminals can cause various problems and damage of component.
Perform checking procedure as follows.
Check damage of harness and terminals : Check terminals for contact resistance, corrosion and deformation.
Check connecting condition of ECM and component connector : Check terminal seperation, damage of locking device and connecting condition between terminal and wiring.
Disconnect the pin which requires checking at mail connector and insert it to the terminal at female connector for checking connecting condition. ( after checking, reconnect the pin at correct position )
Is the problem found?
| ▶ Repair the trouble causing part and go to "Verification of Vehicle Repair". |
| ▶ Go to "Power Circuit Inspection". |
Check power circuit voltage
IG KEY "OFF", ENGINE "OFF".
Disconnect Air-heater relay.
Measure the voltage between power terminal of Air-heater relay and chassis ground.
Specification : 11.5V~13.0V
Is the measured voltage within the specification?
| ▶ Go to "2. Check IG KEY "ON" power circuit" . |
| ▶ Repair problems of Air-heater FUSE in E/R JUNCTION BOX and related circuit and go to "Verification of Vehicle Repair". |
Check IG KEY "ON" power circuit
IG KEY "OFF", ENGINE "OFF".
Disconnect Air-heater relay
IG KEY "ON".
Measure the voltage between coil power terminal ofAir-heater relay and chassis ground.
Specification : 11.5V~13.0V
Is the measured voltage within the specification?
| ▶ Go to "Control Circuit Inspection". |
| ▶ Repair problems of INJ fuse in E/R JUNCTION BOX and related circuit and go to "Verification of Vehicle Repair". |
Check monitoring voltage in control circuit
IG KEY "OFF", ENGINE "OFF".
Disconnect Air-heater relay
IG KEY "ON".
Measure the voltage between coil control terminal of Air-heater relay and chassis ground.
Specification : 3.2V~3.7V
Is the measured voltage within the specification?
| ▶ Go to "Component Inspection". |
| ▶ When voltage is not detected : Go to "2. Check open in control circuit" as follows. ▶ When high voltage is detected : Repair short to battery and go to "Verification of Vehicle Repair". |
Check open in control circuit
IG KEY "OFF", ENGINE "OFF".
Disconnect Air-heater relay and ECM connector .
Check continuity between coil control terminal of Air-heater relay and ECM harness connector.
Specification : Continuity ( below 1.0Ω )
Is the measured resistance within the specification?
| ▶ Repair short to ground and go to "Verification of Vehicle Repair". |
| ▶ Repair open in control circuit and go to "Verification of Vehicle Repair". |
Check Air-heater relay component resistance
IG KEY "OFF", ENGINE "OFF".
Disconnect Air-heater relay.
Measure the resistance between coil power terminal and coil control terminal of Air-heater relay coil.
Specification : 85±5 Ω (20℃)
Is the measured resistance within the specification?
| ▶ Go to "2. Check Air-heater relay component operation" as follows. |
| ▶ Replace Air-heater relay and go to "Verification of Vehicle Repair". |
Check Air-heater relay component operation
IG KEY "OFF", ENGINE "OFF".
Disconnect Air-heater relay.
Supplies random B+ and ground to coil sides of Air-heater relay. ( Coil power terminal, Coil control terminal)
Check continuity between power input terminal and power output terminal of Air-heater relay.
Specification : When power is supplied : Continuity ( below 1.0Ω )
When power is not supplied : Discontinuity ( Infinite Ω )
Is the continuity test within the specification?
| ▶ Go to "Verification of Vehicle Repair". |
| ▶ Replace Air-heater relay and go to "Verification of Vehicle Repair". |
※ Repeat this process 2~3 times.
After a repair, it is essential to verify that the fault is corrected.
After connecting GDS select "Diagnostic Trouble Codes(DTCs)" mode to and then clear DTC.
Drive the vehicle within DTC Enable conditions in General information.
After selecting "Diagnostic Trouble Codes(DTCs)" mode and check DTC is recorded again.
Are any DTCs recorded ?
| ▶ Go to the DTC guide of recorded NO. in GDS. |
| ▶ System operates within specification. |
