2532 done a wedding today, running sweetly, dropped off the wedding party at their venue, then it failed to start! Click from the fuel solenoid, no start, no gears. Isolate everything, start again, click, no start no gears. The it started, but no gears. So switch off, try again, nothing.

Call home, get a lift back with tools; check wires to gearbox ok, wires to gear selector ok, disconnect control panel, engine starts, but no gears of course.

So, do the usual by-pass wiring to get me home and wonder what the actual problem is. Maybe the panel thinks the engine's already running; maybe it's the handbrake switch gone defective and refuses to let any gear select..any ideas? I need the auto panel as that feeds the tacho.

My bus number (if any): RML2532

Which reminds me I had a similar problem on a Cummins RML in Germany earlier this year; the owner reported no air at the gearbox. I went prepared to resolve an air problem, only to find it was an electrical problem, no feed fro the panel to the gearbox; continuity on the 7-core to the gearbox was ok, but nothing getting through the control panel. I suspect this may be the same problem on this bus as mine.

The EF Language School bus (Scania engine) suffered a similar problem in Italy.

We really need to get to the bottom of this to find the root cause. The CAV book on the modified panel says they are the most reliable with only 2 failures on the DMS fleet in 5 years (oh yeah?) so why are we now seeing more failures on RMs? Are the problems all being caused by negative earths on the bodywork?

My bus number (if any): RML2532

Roy

Have you checked the 551 unit (control board fuse) which has a 5 amp rating.

Yes, that was ok.

My bus number (if any): RML2532

Well, the 2 errant panels are now on the way back from repair at PSV electrical; according to their service manager one unit had a broken 3-pin connector (presumably the speedo drive plug from the sender unit), and both had several dry joints inside the circuit boards.

There is a possibility that there could also be problems on the vehicles, so I'll have to keep a check on that too.

My bus number (if any): RML2532