power seats

[Mike Humble]

We have 2008 Contessa.  Had captain's seats removed for uphostery.  When returned drivers seat was plugged in and worked.  10 minutes later tried again and didn't work.  Checked power to plug. OK.  Seat side of plug OK. Disassemble seat to check power.  Have power to 6way and out of 6way and to motors.  All have power.  Voltage is 16-20v.  Nothing moves.  Anyone have any ideas.
Mike

[Dennis Crawford]

Are you sure the voltage is in the 16-20 volt range?  That is very high for a 12 volt system.  Motors could have been damaged.


Dennis

[Mike Humble]

Thanks Dennis,
Checked two other VOM's and got 13.3.  Bad battery in first one.  I was worried about that too.
Mike

[Edward Buker]

Dennis,

You can have a connection that is good enough under no load to read voltage but when you use the seat button and connect the motor in the on position and pull current the voltage could drop severly due to resistance possibly in the plug or switch. Try measuring the wiring that goes into the motor after the plugs and switch and see what you get for voltage when you hit the power on button for the seat movement. If it is about 12v and no motor noise then you have an issue with the motor. If it is much les than 12v you could have a bad connection (resistance) that is dropping the voltage causing the motor to not operate.

Later Ed

[Mike Humble]

Tested this morning and got the same results on both chairs.  Input voltage at switch is 13.3 volts.  When any function on switch is activated, the voltage both after the switch and the input voltage drop to .4volt.  Must be a short somewhere.  Would it be before or after the switch?
Mike

[Edward Buker]

Mike,

If the voltage drop can be measured and you see it before the switch then the high resistance causing the voltage drop is before the switch. Check before the plug by using the button for the seat and  keep following the wiring back to a breaker. Wherever you stop seeing the voltage drop, like before the breaker is good at 13V and after the breaker has the drop then that result would tell you that you have found the source, in this example the voltage drop is in the breaker.

Later Ed

[Mike Humble]

Ed,
Thanks.  I put the meter on the wires entering the seat (berfore the switch) and got the voltage drop.  Now does anyone have an idea where the power comes from for the seats.  I can't find any mention of power seats on any of the fuse panels or breakers or in the schematic.
Mike

[Joel Ashley]

I don't know if your coach is the same as ours in where the seat breaker is, but ours is circuit breaker 10 (25 amp) down from the top of the middle breaker buss.

If you had a LAN tracker, you could trace from the switch to the correct breaker posts.

Joel

[Tom and Pam Brown]

I think it may be time to use another power source directly to the motor to see if it works.

[Steve Jewell]

Mike, It sounds like you my have a ground problem. To check this run a wire from a steering column mounting bolt to a bolt on the base of the seat and see if it works.

 Steve J

[Gerald Farris]

Mike,
From your description, you do not have a ground problem. If the voltage drop at the switch returns to normal (13+ volts) as soon as you let off of the switch, Ed is probably right that the problem is high resistance before the switch. However, if you have to wait a minute or so for the voltage to return to normal as the circuit breaker cools, you probably have a short to ground between the switch and the motor.

Gerald  

[Mike Humble]

Just checked and it returns to 13.3 immediately after releasing switch.  Will get a tech out in the next couple of days.
Thanks to everyone for all the help.
Mike

[Edward Buker]

From the seats the wiring from the harness  probably goes through one of the round amphonol black plugs in the electrical bay and then to a breaker. Could be a bad contact in the plug or a bad breaker contact. Just a couple of spots to look that could be good candidates for the tech...good luck on your hunt.

Later Ed

[Steve Huber Co-Admin]

Mike,
From your description of the problem, it sure sounds like the problem is in the connector that the seat plugs into, the one they unplugged to remove the seat. My 01 Contessa has a 2 wire connector under the seat. If you haven't already done so, check voltage / on both sides of the connector. I'd also unplug it, spray it with contact cleaner and replug it a couple of times.
Good luck,  Steve

[Mike Humble]

All fixed.  It was a circuit breaker in electrical bay. Thanks to all for the help.
Mike