[mickinuk]

I came across your message and thought I would include my DPF experiences over the last few days. We have #1277, so a very similar coach. I had error codes 318-4 and 320-4 "/LOVOLT". They were intermittent for the last few months but became persistent. Then Sunday I had 151-0 and finally 151-11 "DPF1 SOOT LOAD HIGH", followed by a derating to 50% power, and finally, the dash flashed "STOP ENGINE".

I stopped within a couple of miles because the next event would be a forced engine shutdown. A recovery truck took us to Peterson Cat, Medford, OR, who were excellent.

The errors were sensors on the curbside DPF filter, which were reporting short to ground, disconnecting them reported stuck high, which confirmed it was the sensors. The sensors were in stock and cost about $600. Once the sensors were fitted, the engine was forced into regen, and the problem was solved.

The short version is, don't ignore the 318-4 and 320-4 "LOVOLT" error messages because they prevent regen, which will bite you in the end.

I still have an intermittent 328-4 "/LOVOLT" which is an air temperature sensor on the input to the ARD (the diesel burner that does the regen), but it's nearly impossible to reach behind the engine. I have a leaking charge air cooler, which will be replaced in January, so the sensor will be accessible and replaced.