Are you getting intermittent behaviour when you press control button, functions not always operating until the pump gets a thump?  Does your pump freeze upon power on? A permanent E05 even after replacing the temperature sensor?  This would suggest your pumps logic controller has failed.

Connections are as follows:
 
Blue 2 pin - Thermal Fuse
Black 2 pin - Flow Sensor
Red 2 pin - Thermostat
Black 4 pin - Control Panel
2x Clear Spade Connectors - Thermal Cut Out
 
This logic controller has been removed from a legacy 'Egg' shaped Lay-Z-Spa AirJet Pump.  Please be aware that it will only be compatible with a 4 pin control panel of the Mk4 design (as pictured).  The same connector is used in the Mk2 and Mk3 but they are not compatible.
 
Royal Mail Tracked Shipping to UK addresses is included in the 'Buy it Now' price.  For orders outside of the UK an additional postage charge applies for International Tracked Shipping.
 
The Spa Workshop Ltd is based on the edge of the New Forest near Southampton in the United Kingdom.  We specialise in the servicing, parts and repair of Bestway Lay-Z-Spa AirJet and HydroJet pumps.  If we can be of assistance in resolving your spa pump issues, please do get in touch.
 
All items are shipped worldwide, Monday to Friday.  We aim to provide all of our customers with excellent products and service, if you experience any issues please contact us, we are always happy to help.