Removal and installation of the preheating control unit
1. Disconnect the negative battery terminal.
2. Remove the battery from the shelf.
3. Disconnect the connector and remove the preheating control unit.
4. Installation is made in an order, the return to removal.
Checking the preheating control unit
1. Perform self-diagnosis with the ignition on and the engine off.
2. Check for fault codes related to the preheating system. If such codes are found, carry out the appropriate repair work. If no trouble codes are found, go to the next step.
3. Check the preheating control unit for damage.
4. Check the preheating control unit connector for damage or corrosion.
5. If any defects are found, repair or replace the defective component.