On a short trip last weekend our red Check Engine Light turned on followed by a blue Engine Warning light. I noticed the Dash Temp reading was not even in the scale, it was pointing directly left.
The cycle repeated about 5 times in a 20 minute span. The engine also reduced power and slowed to about 45 mph. This cleared up as soon as the lights went out.
Aladdin showed Engine temp at 204 and transmission at 212 during this episode.
I checked coolant and the reservoir was fine but there was a little fluid on the bottom tube of the reservoir and on the lower coolant hose. I tightened the hose clamps and looked for anything else disconnected. Wires near the cooling sensor are exposed as the black wire loom has deteriorated and one wire appears cut, probably from previous service, i didn't find another loose wire it could have connected to. I plan to replace the wire loom and double check the conductors for damage.
I looked in wire schematics but none show how the dash gauge connects to sensors or the ECM. The light works on it and there are three other wires connections all sound.
About a month ago I rebuilt the seals on the Hydro pump solenoid, my first trip it ran hot and cut back at 225 degrees, I adjusted the solenoid and the next road test was fine and have put over 1000 miles on since with no issues.
If you made it thru all of this, nice job!
Update #1
The local Freightliner service center replaced the oil pressure sensor. Then tried to test drive the coach; oil pressure read a steady 57 PSI and never changed. When the coach was put in drive, it immediately lost power and could not be driven. They had to return to the service facility in reverse! That was the only way they could get it to run with power. After talking to a CAT service advisor they decided to flash the ECM. This enabled the new sensor to give proper readings that fluctuated with engine RPM. However the power issue remained; they are stumped at what to do next. The only thing they noticed was turbo readings are at 0 so they're thinking it could be a faulty sensor there. They're planning to swap out that sensor tomorrow. It never showed any other check engine lights but just won't run. They suspect that something could be happening on the 5 volt sensor bus affecting operations.
Update #2
They replaced the Turbo Pressure sensor today and called to saw it is now fully resolved. I hope to be able to pick it up tomorrow and road test this week!