A member with a 2014 Montana reported that the hydraulic slide outs only make a humming sound when trying to open them, despite having a new battery and being connected to shore power. Members focused first on electrical causes, especially testing the pump motor and solenoid, checking the resettable DC breaker feeding the pump solenoid, and noting that some units originally had a 50 amp breaker that was later recommended to be upgraded to an 80 amp breaker.
Other suggestions included...
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A member with a 2014 Montana reported that the hydraulic slide outs only make a humming sound when trying to open them, despite having a new battery and being connected to shore power. Members focused first on electrical causes, especially testing the pump motor and solenoid, checking the resettable DC breaker feeding the pump solenoid, and noting that some units originally had a 50 amp breaker that was later recommended to be upgraded to an 80 amp breaker.
Other suggestions included checking the rocker switch, verifying hydraulic fluid level, looking for leaks, and tightening solenoid connections without overtightening. The discussion did not confirm a final repair, but the main likely areas identified were the breaker, solenoid, pump motor, switch, fluid level, or loose electrical connections.