Protecting Motor From Overheating

In order to protect the sunroof motor from overheating from continuous motor operation, the sunroof ECU controls the Run-time and Cool-time of the motor as follows:

1. The sunroof ECU detects the Run-time of motor
2. Motor can be operated continuously for the 1st run-time (120 ± 10sec.).
3. The continuous operation of motor stops after the 1st Run-time (120 ± 10sec.).
4. Then Motor is not operated for the 1st Cool-time (18 ± 2sec.).
5. Motor is operated for the 2nd Run-time (10 ± 2sec.) at the continued motor operation after 1st Cool-time (18 ± 2sec.)
6. The continuous operation of motor stops operating after the 2nd Run-time (10 ± 2sec.)
7. Motor is not operated for the 2nd Cool-time (18 ± 2sec.).
8. Motor repeats the 2nd run-time and 2nd cool-time at the continued motor operation.
   • In case that motor is not operated continuously, the run-time is increased.
   • The Run-Time of motor is initialized to "0" if the battery or fuse is reconnected after being disconnected, discharged or blown.
   Fig 1: Sunroof Switch On/Off Pattern

   Courtesy of KIA MOTORS AMERICA, INC.

   T1: 120 ± 10 sec., T2: 18 ± 2 sec.,

   T3: 9 ± 2 sec., T4: 18 ± 2 sec.