2004 Patriot Thunder Starting Issue

[Randy Stephenson]

Mike:

Thank you for the continued trouble shooting help.  Carefully listening in the front compartment indicated a circuit breaker was kicking on and off.  Hence, the clicking sound I heard a few days ago and suspected the starter solenoid.   

I just removed and checked the diode, it shows as shorted.  So as a test,  I removed the diode from the solenoid and now have dash power.  However, I'm afraid to try starting the coach until a new diode can be found.  Do you all think it is OK to start the coach without the solenoid diode?

Thanks to all for the support, hopefully, this solves the no-start dilemma!  I'll advise once I find and install a new one.

[Randy Stephenson]

Mike:

The picture, notes,  and band information is very helpful.

Thanks, Randy

[Mike Shumack]

Mike:

I just removed and checked the diode, it shows as shorted.  So as a test,  I removed the diode from the solenoid and now have dash power.  However, I'm afraid to try starting the coach until a new diode can be found.  Do you all think it is OK to start the coach without the solenoid diode?

The diode is there to prevent a voltage build up (and then a potential spark across the ignition switch contacts and to prevent that voltage build up (spike) from harming any sensitive electronic components on that same circuit) when the power to the coil is cut off.  When the voltage to the solenoid's coil is cut, the magnetic force created by the the coil collapses and creates an induced voltage back through the power circuit (ignition wire in this case) that was feeding the coil. So the diode was added to prevent that voltage spike.

To answer your question - Yes, you can remove the diode and you will probably never see any negative effects. IMHO. But I would get a replacement and reinstall it as soon as possible regardless. I believe the part number is IN5400 SB560 (maybe someone else can confirm this - or check wirth BCS)

Here's a good video explaining the purpose of that diode (note that in the video diagram, author shows master switch completing the ground circuit for coil. On our coaches the master switch (ignition switch) is providing the power to coil, and ground is already present.
https://www.youtube.com/watch?v=bvDuyM2e4gw

[Randy Stephenson]

Mike:

Thank you for your expert advice!  I found a diode (part number was on mine TCI 1N540, it's a 3 amp rectifier diode) from a distributor in Florida, the cost $.20 each. I have five coming for a $1.00 and $9.00 two day priority shipping.

I learned a lot on this situation, your info about the diode got me thinking and I did a check, results was a shorted reading on the multimeter (my first experience in this area), who would of thought a clicking breaker sound was due to a shorted diode.....assumed battery condition or the solenoid was the issue!  I'll confirm it's the fix once I install the new diode.

Randy

[Randy Stephenson]

Steve:

Thanks for your help,

Randy

[Mike Shumack]

Mike:

 I found a diode (part number was on mine TCI 1N540, it's a 3 amp rectifier diode) from a distributor in Florida, the cost $.20 each. I have five coming for a $1.00 and $9.00 two day priority shipping.

Randy

Thanks for providing the correct part number.  Now that you will have five Diodes in your tool box, your guaranteed to never need the other four.  LOL.
And $9 to ship $1 worth of parts - well I've been there too.

[Randy Stephenson]

Definitely, Thanks again!

[Randy Stephenson]

Steve and Mike:

 I installed a new starter solenoid, and solenoid diode, along with chassis batteries.  The coach is now starting great.  It turned out that a cell was bad in each chassis battery.  Steve's earlier post about a potential battery issue was on target. 

Seems that the batteries were most likely the starting issue I had experienced upon departure from Breckenridge , CO for the drive back to my Michigan home base.  What threw me off was the coached started just fine at fuel stops and even after a seven hour sleep stop at Cabelas parking lot in Nebraska. So, I did not consider batteries as the issue and went directly to replacing the starter solenoid.

Fortunately, today, I was able to move the coach into the barn for the winter; unfortunately, I will not be on the road again until after the Spring snow melt.

Thanks again for your help and advisement on my starting issue.

Randy

[Michael Peters]

My coach recently had a similar starting issue. Good voltage , but sluggish and intermittent starting. I have already upgraded solenoids in electrical panel.I moved to the starter itself and found the connections loose. After tightening them it works great. Its an easy check