Rear Doors Bug

[moosemanusa]

Whilst this maybe more RTS, i'm pretty sure these door systems are installed in many different buses.

Have a set of rear doors.. worked perfectly until someone pulled the emergency cord.

Now they will open, close normally but will not disengage the interlock (meaning the bus will not move and the door can be pushed open still).

I simply have to reach above and push the actuaator arm in and fiddly with the interlock connector and pshhhh the door is now locked and all is good..

I've seen this happen to 2 different buses, so i'm guessing maybe there's a clip that breaks when the emergency is pulled but have not found any real evidence of this.

Door mech company are no help either, they claim they didnt make the system even though they're name and number are on the plate

Any ideas?

[Runcutter]

Details on the bus?  I have a maintenance manual for RTS-04 series from when I bought a fleet of them -- if there's something you want me to look up tomorrow.

Arthur

[moosemanusa]

This ones a 96 tmc/novabus (its the x-over year so its a pain) but have the same doors as the 4.

It was similar door system on the new novabuses (98 to 02)

Now I have the parts break down but not the reset procedure after the emergency cord has been pulled or if there is some new part needed once its been pulled..

Thanks

[Runcutter]

The only thing I can find in the RTS/04 manual is "An emergency release microswitch is located on the emergency release valve mounting bracket.  It is actuated by the handle of the emergency release valve.  With the door master switch in the "on" position, and the emergency release valve handle in the down "release" position, 24 volts is directed to the brake interlock relay and magnet valve, lightly applying the rear service brakes.  When the handle is returned to the normal "up" position, the circuit is broken and normal coach operation can be resumed." 

So, it appears the restoring all handles to the normal position would restore normal coach operation.  Thinking about transit service, this makes sense -- don't want a bus out of service for minor stuff.  I don't know if this helps, but I'd check the microswitch on the emergency valve.  I can't tell if it's normally closed or open, but the way I read the above, I think it should be normally open -- actuating the emergency handle closes the switch and activates the interlock.  If the switch is stuck, try removing one of the wires -- taking the microswitch out of the circuit and see if that solves the problem.

If that's not it, the only other thought I had is if there is/was a rear door wheelchair lift, and something in that circuitry got fouled up.

Otherwise, I'm stumped.

After solving the current problem, find a way to channel high voltage to the emergency release handle itself, with appropriate signage, so there's a disincentive to anyone thinking about fooling with it in the future.

Arthur

[moosemanusa]

I've had this problem on 2 buses now, I even swapped this unit from another bus that used to work, once installed it did the same.. The emergency pull handle is back in its position.. I'll try and snap a video later as this is something thats bugged me for 2 years now. we dont even use the rear doors but you know.. those annoying problems..

[oltrunt]

Runcutter, I like the way you think!


"After solving the current problem, find a way to channel high voltage to the emergency release handle itself, with appropriate signage, so there's a disincentive to anyone thinking about fooling with it in the future"     Jack

[moosemanusa]

there's a nice 24v line by the handle.. A well placed capacitor could be handy