Newell Gurus

My check Transmission light comes on periodically at speeds above 55mph. Please share any knowledge of cause and posable solutions.

Mine will do the same if I am running a roof AC off the inverter/engine alternator with emergency start on. Problem goes away if I start genny (all batteries are under a year so it is not a battery issue). Spoke with Newell and they concur that, notwithstanding the literature or sales talk, roof air should not be run without genny and resulting power drain may be affecting ZF that requires stepped up 24 volts.

Not sure if this is applicable to your situation?