Patriot Thunder Stops Running

[Lee Welbanks]

A month ago coming across Oklahoma on I 40 the coach would just plan shut off and then restart. At the time I thought it h. d something to do with the cruise control so turned it off. The coach ran find until we got to Little Rock Ak I took it into Riggs Cat to have their truck tech dump the ECM and see if we could spot anything, of course it ran great and the ECM showed nothing. Going out the gate it quit running, went around the block and it quit about 4 times, back to Cat, went through everything again, RRun box with all its circuit boards, checked fuses nothing. Ran great Tn, La, Fl up to S Carolina did it a couple times. I thought it might be the Front/Rear switch in the run box so I turned it over, ran fine. Started up the other morning to leave and it quit again and again. Every time it would dye I would check the run box and the panel would be dead, then I pushed on the PCB 1 board (started control board) that sends power the the rest of the boards and it would light up, push and pull on the board and it would go on and off on and off.
Ordered a new 73-00825 from North West Rv, 2nd day air, received today and installed and the PT is back again. Leaving tomorrow for Raleigh NC.

[Edward Buker]

Lee,

If the dash gauges also shut down at the same time that the engine shuts down then the solenoid at the bottom of the two copper busses in the electrical bay below the driver's seat will cause that symptom of shut down. The contacts in the solenoid will make marginal contact with age and can be intermittent. In an emergency or for trouble shooting you can jumper the two large contacts with a suitable gauge wire to see if the problem goes away but you will have to unbolt the wire to shut down.

Later Ed

[Lee Welbanks]

Ed, The new board has curved this issue.

[Edward Buker]

Lee,

Great job finding and fixing your problem, that one was more obscure then the usual suspect. Enjoy your travels this summer.

Later Ed

[Stan Simpson]

Lee, glad you are back on the road. For future reference, where is that board that you replaced located? It still might be different on our Monterey, though.
Stan

[Joel Ashley]

Im not sure the Monterey has a "rear run box", Stan.  I've never seen one, but haven't looked either.  It's mounted to a frame rail near the engine and used on some rigs to start the engine from there, handy for service techs, etc.  The PCB (printed circuit board) Lee replaced in the box may be the one in the link below.

Joel

http://www.ebay.com/itm/152495347804?vectorid=229466&item=152495347804&rmvSB=true&ul_ref=http%253A%252F%252Frover.ebay.com%252Frover%252F1%252F711-53200-19255-0%252F1%253Fff3%253D2%2526toolid%253D10001%2526campid%253D5338027161%2526customid%253Dpcb-50.53.138.213%2526item%253D152495347804%2526vectorid%253D229466%2526srcrot%253D711-53200-19255-0%2526rvr_id%253D1228198555926&ul_noapp=true

Often I've repaired PCB's like this situation where a solder point has cracked or a connection has simply loosened, as his symptoms indicate.  But it's not breaking the bank to just replace the board and move on.

[Lee Welbanks]

The rear run box is mounted in the right side in the engine compartment, it has all the contol boards for the motor, batteries, and the fuses and circuit breakers for the power reels .and more.
I think the problem with the board is a bad relay, I can hear somthing making and breaking connection when I move things around. Just a guess, can't see any prob with the soldering.

[Joel Ashley]

No, it's really hard to see solder cracks.  I've had to use special magnifying lenses to examine solder points for connectors, diodes, transistors, capacitors, you name it.  Sure enough there's often a nanocrack barely visible even magnified.  Or some minor flaw on a PCB trace.  It means incomplete contact so it doesn't take much to break and then reconnect a circuit, then break again. And yet it's enough to stop a Mack truck... or a Beaver.

I've had several things go askew due to that, from a simple solar outdoor lantern to our 1994 microwave that service techs couldn't fix.  Aw, just buy a new one they'd say.  A new one that was similar but not as good was over $500, and it just took my sheer determination to eventually spot two infinitesimally tiny crack lines on the master PCB.  A couple dabs with the solder iron and it was good as new again.

Joel

[Lee Welbanks]

Joel, I fixed the circuit board for my Girard awning that had a bad solder job on one pin. When we get back to Az this fall  I will run this board through the ringer to see if I can find the flaw.