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Old 09-14-2019
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RVinCT RVinCT is offline
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Join Date: Jan 2018
Location: Rockfall
Posts: 400

The oil pressure:
It appears that there are two places where oil pressure can be measured. One is on the passenger side. That seems to be where Doc installed his adapter OP gauge. It's a metric thread. That location can be seen in the drawing of his adapter posted in this thread.

The second is on the other side (driver side) where BB installed their VDO pressure switch, which feeds the front and rear OP gauges in the BB and where I installed my mechanical OP gauge.

That location is a 1/8" NPT fitting as are many OP gauges, including mine. I bought a "T" female 1/8" NPT fitting and a "short" threaded male-male pipe that threaded into the block then into the T. It's very tight in there, which is why the short male-male was needed. I mounted the gauge in the left rear.

I'll eventually replace the VDO sensor since it currently reads zero when the pressure is really 25 psi. I imagine it has just gotten old and inaccurate.

Engine ECU power problem:
As to the actual engine shutdown and alarm/check engine light problem, it was the intermittent power to the engine ECU causing those issues (I think). There are supposed to be three 7.5A fuses feeding the Engine ECU power. Those fuses should be in the rear PDU next to the engine batteries. The wires can be seen in the schematic "Rear Cummins PDU" that BB supplied and in the Cummins schematics. The wires are labeled 1111D to 1111F. However in my rear PDU, only one of those fuses was labeled correctly. The other two were marked "Spare". If you look in the rear of the fuse panel, you find the correct wires, and I traced them to the ECU. They had the correct fuses in only 2 of the three locations. I don't know if that contributed to my problems, but I fixed it. If anyone tried to use the mismarked "spare" fuses, they would remove power from one of the required power wires to the engine ECU. The Cummins diagram also shows two 10A fuses supplying power to the ECU. I was able to verify that those two wires had power at the ECU, but I never found the fuses. They didn't seem to appear in the BB schematic.

BTW, it takes a 4mm hex Allen wrench to remove the two engine ECU power cable connectors from where they attach to the ECU on the engine block. There are 50 pins in each.

The old RoadRunner4 gave me the correct Cummins Fault Code of 434. The new Silverleaf did not. The info may have been in the Silverleaf codes, but not in the numbering that Cummins uses. Without the RR4, solving this would have been very hard as the power problems were spitting out lots of codes to the Silverleaf.

Finally, there was an odd issue with the engine compartment lights. They only have power with the front ignition on. I traced the BB schematic and it looks like they should turn on whenever the light switch in the engine compartment is on, regardless of whether the ignition is on. I don't know if other people have to turn on their ignition to get those lights to work. Eventually I will rewire the fuse box so I can turn them on without the ignition. Perhaps BB changed the design, or maybe it was my dealers hack job rearing its ugly head again.
Todd and Karen Pattist
Rockfall, CT
2007 Double Slide M380 "Bertie"

Last edited by RVinCT; 09-14-2019 at 08:40 PM.
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