SL300 defrost

[giath]

Please any help, I have thermo king Sl 300 .
when degree becomes 5 C the unit does not run defrost
thank you

[cadwaladr]

does it defrost when its at 0,what are the other temps air outlet/discharge air/coil sensor?

[gravy258]

the coil has to be at + 7.0 c before defrost is initiated

[giath]

when I do manual defrost the fuse 3 blown.

[cadwaladr]

sounds like damper door problem ,what does fuse 3 protect,does it not say on the panel door you have opened to access fuse?

[giath]

Thank you sir
I found the fault which is shortage in damper motor 29 wire.

[cadwaladr]

your very welcome.