Sorry - Yes we do have 5v between the red and black wires on the 5 way connector.

 

The next bit - The voltage on each of the blue, yellow and green wires, while rotating the wheel slowly backwards does not pulse at 5v. There is voltage there - 0.2 - 0.3 but not pulsing.

That would mean that the hall sensors in the motor are blown. It's possible that heat damaged them when you were going too slow up the hill. Other possibilities are that the wires in the controller compartment melted, but you would have seen that, or the motor cable is damaged and one of the hall wires shorted to a phase wire. Check the motor cable for damage, especially where it comes out of the axle.

 

If there's no short and it's only that the halls blew due to heat, you can replace them, which is a little bit tricky, but OK for anybody that's used to fixing things. They cost next to nothing. Use Honeywell SS41 or equivalents. Alternatively replace your controller with a sensorless or dual mode one, which costs about £40 with an LCD. you have to rewire a couple of connectors to fit your bike.

 

https://uk.banggood.com/24V36V48V60V-250W350W-LCD-Brushless-Motor-Controller-Battery-Speed-For-MTB-E-Bike-Scooter-p-1399444.html?utm_source=googleshopping&utm_medium=cpc_organic&gmcCountry=GB&utm_content=minha&utm_campaign=minha-gbg-en-pc&currency=GBP&cur_warehouse=CN&createTmp=1&ID=520456516800&utm_source=googleshopping&utm_medium=cpc_bgcs&utm_content=sxxx&utm_campaign=ssc-gbg-all-0218&ad_id=332556156911&gclid=Cj0KCQjws-OEBhCkARIsAPhOkIbDVOSYbq4ldHlSdZ6tSISLHVPzLdeUdSkrNcXzPYA8qaFWPKPBHcoaAjUrEALw_wcB

That would mean that the hall sensors in the motor are blown. It's possible that heat damaged them when you were going too slow up the hill. Other possibilities are that the wires in the controller compartment melted, but you would have seen that, or the motor cable is damaged and one of the hall wires shorted to a phase wire. Check the motor cable for damage, especially where it comes out of the axle.

 

If there's no short and it's only that the halls blew due to heat, you can replace them, which is a little bit tricky, but OK for anybody that's used to fixing things. They cost next to nothing. Use Honeywell SS41 or equivalents. Alternatively replace your controller with a sensorless or dual mode one, which costs about £40 with an LCD. you have to rewire a couple of connectors to fit your bike.

 

https://uk.banggood.com/24V36V48V60V-250W350W-LCD-Brushless-Motor-Controller-Battery-Speed-For-MTB-E-Bike-Scooter-p-1399444.html?utm_source=googleshopping&utm_medium=cpc_organic&gmcCountry=GB&utm_content=minha&utm_campaign=minha-gbg-en-pc&currency=GBP&cur_warehouse=CN&createTmp=1&ID=520456516800&utm_source=googleshopping&utm_medium=cpc_bgcs&utm_content=sxxx&utm_campaign=ssc-gbg-all-0218&ad_id=332556156911&gclid=Cj0KCQjws-OEBhCkARIsAPhOkIbDVOSYbq4ldHlSdZ6tSISLHVPzLdeUdSkrNcXzPYA8qaFWPKPBHcoaAjUrEALw_wcB

 

Cannot thank you enough for all your help. We will now follow through on your last message and let you know how it all goes. Will check the motor cable but visually it looks ok. Thank you for the controller link too.