BAC Forum

General Boards => Technical Support => Topic started by: Mark Hoovler on June 07, 2024, 10:33:25 PM

Title: Electrical glitch
Post by: Mark Hoovler on June 07, 2024, 10:33:25 PM
Pulled the motorhome out of storage and the steps keep going in and out and the power to the dash instruments goes on and off.  What would cause this type of operation.  Should I be looking for a short in the wiring somewhere?

Appreciate any help,

Thanks much

06 Monterey Laguna 4
Title: Re: Electrical glitch
Post by: Steve Huber on June 07, 2024, 11:15:22 PM
Mark,
Assuming they are related, check the voltage at the ignition solenoid. If ok check at output of CB 36 and CB 37 to see if voltage is constant.
Steve
Title: Re: Electrical glitch
Post by: Carl Boger on June 08, 2024, 12:01:17 AM
Mark,

As Steve suggested,I would start by checking the voltage to the switch and at the switch.  If the stairs think the engine is being started they will retract.  If the door is open they will try to extend.  I would also check the ground to the switch and dash.

Most steps have a plug on them that you can simply unplug to see if the two issues are related or if one goes away when the steps are taken out of the equation. 

Hopefully this will be an easy problem to fix
Title: Re: Electrical glitch
Post by: Mark Hoovler on June 08, 2024, 01:09:04 AM
voltage seems to go in and out
Title: Re: Electrical glitch
Post by: Steve Huber on June 08, 2024, 03:34:19 AM
Is voltage varying at the ignition solenoid or at a circuit breaker? Which one? If at a circuit breaker but not at the solenoid it is either a bad circuit breaker or an overload (short) downstream from the breaker. If at the ignition solenoid, check for a problem in the rear run box.
Steve
Title: Re: Electrical glitch
Post by: Mark Hoovler on June 08, 2024, 03:19:26 PM
Is the run box in the rear  where the big solenoid is located? 
Title: Re: Electrical glitch
Post by: Steve Huber on June 08, 2024, 05:23:14 PM
Yes, Should be rear bay on pass side. Was voltage varying at solenoid?
Steve
Title: Re: Electrical glitch
Post by: Mark Hoovler on June 08, 2024, 07:33:07 PM
The voltage at the solenoid was 7v dc.  After going thru all the circuit breakers again.  CB-9 seems to be the culprit with a short to groundon one of the legs/wires coming off the breaker.  Next task will be to find the short on that circuit.  (bay lights/batt. outlet)
Keep you posted.
Thanks
Title: Re: Electrical glitch
Post by: Steve Huber on June 08, 2024, 08:27:13 PM
Mark,
With the wire that shows gnd disconnected from CB9, does the battery voltage go up to 12V+? If not, charge the batteries before trying to track down anything (other than the short to gnd) as low battery voltage can result in some weird symptoms. Be sure to chk voltage on both chassis and house batteries.
One other item, did you have the  engine running when you noticed the varying battery voltage? If not were you on shore power, generator or batteries?
Steve
Title: Re: Electrical glitch
Post by: Joel Ashley on June 08, 2024, 11:22:02 PM
I have to agree with Steve, the first thing to check is voltage at the batteries.  If for some reason the engine would crank and start, but bats weren’t subsequently at full power and the alternator not working when you came out of storage, low chassis voltage can cause the symptoms you describe.  Indeed, devices of all kinds, 120v, 12v, 3v, can behave with on/off cycling, etc., when diminished voltage pushes incomplete current.  Remember that many an alternator has gone belly up trying to replenish banks that weren’t first charged via post or genset.

Joel