Key won't start the engine

[Robert Green]

I tried to crank our 02 Patriot Thunder this evening. Dash powered up.  Transmission panel has power.  I hear a click when I turn the key but the starter is not engaging.

Coach and chassis batteries are all brand new.  Checked voltage and they seem fine. 

In the front left bay I jumped the solenoid. The electric fan kicked on, but nothing further.

Reading this thread there is mention of a second solenoid located in the back bay.  I found one last week (while working on a fix for the main slide) that is bolted to the ceiling of my battery compartment. If the 2002 Patriot does indeed have a second starter solenoid, might this be it?

[Edward Buker]

Bob,

There are typically two solenoids back there, one parallels the two battery bank for emergency start which you could try and see if it makes a difference. There is a second one that goes to the salesman switch that shuts down many systems in the coach. You could listen at the solenoid and have someone run those switches to see what does what. When you say you jumpered the solenoid in the electrical bay I assume you jumpered the large leads which would have been correct. If the transmission pad lights and the dash gauges come on with the key then that solenoid in the electrical bay under the drivers seat is working.

There may be a small relay that shortens the wiring path to the winding that triggers the starter solenoid rather then using the key directly. If the solenoid at the starter clicks then the wiring path from the switch, whether it uses a relay in the back or not, is working OK. It could be the starter solenoid on the starter, the starter itself, or the heavy cable + or ground connection that power the starter. I would be looking at all the heavy cable connections between the battery and the starter to see if they are clean and corrosion free. There should be + 12.8 V or more on the large lead on the starter solenoid. If you can safely check the voltage on that terminal to ground when the key is turned to the crank position, that will help sort this out.

Later Ed

[Dave Atherton]

Robert, this may sound kinda off the wall with your starter all of sudden just clicks at solenoid. May
I make a suggestion. Have someone turn key switch on all the way like it will start. Than take a hammer
and tap on the starter while key is in start. This may surprise you it may start. Starters in time will stop at a dead spot and the little tapping on housing it is all it needs. Would try this before you start taking things
apart. Than think about a starter replacement. Cat has OR-Remain program, starter will save you lot of
money. Doing Cat field service repairs many years have ran into your problem many times.
Dave Atherton RetiredCat mechanic

[Al Lewis]

On my 2002 Monterey I had the engine running ready to leave a rally and the lights on the transmission pad went out. It would not go in gear. After killing the engine by turning the key off the engine would not crank with the key. I found that it would start using the controls in the engine bay (where the fuel filters are). Six days later, a 70 mile tow to Dallas, a knowledgable tech, and several $1000 the Allison computer was replaced and everything worked. I hope (and don't believe this is your problem. This is the only time in 11 years I have been stranded so can't complain. But check out the start switch in back.

[Robert Green]

Dave, Ed, Al
Thanks so much for the thoughtful input.  I'll get a second man and see what I can find when they work the key starter up front. 

The rear starter button has never worked for me since I've had the rig (about a month now).  Kill switch worked just fine the one time I tried it.  I was able to restart via the ignition key afterwards.

A sidebar question - When shutting the motor down via the ignition key, I noticed that the motor will run for a few seconds after the key has been moved to the off position.  Is this "normal" operation? 

[Dave Atherton]

Robert, shut down is not normal. this sounds problem within the key. There is a bulletin out on
Ignition key switch circuit and battery supply circuit. if you have silver leaf here is the following
codes 168-02 ECM battery power intermittent, code 168=01  Low ECM power, Code 43-02 Key
switch fault.  the ECM receives electrical power (battery voltage ) through the wiring that is supplied
by the vehicles equipment ( OEM ). Keyswitch recieves battery voltage from keyswitch is in the ON position or in the Start position. When the ECM detects battery voltage at this input, the ECM will power up.
When battery voltage is removed from this input , the ECM will power down. Info. for C-12 2KS00001-up
Dave Atherton Retired Cat Mechanic

[Robert Green]

Dave
Greatly appreciated. I'll check for codes.

I did get a helper and was going to give the starter a couple taps when it occurred to me that I had not checked the batteries as I originally stated. Both chassis batteries were reading about 10 volts. So my shore power hook up is not maintaining my batteries (that were installed about a month ago). I have a charger on them now and will see if that resolves my start issue later this morning.

I'll add the charging issue to my list. I was concerned I would run out of things to spend money on and to fix. 

[Dave Atherton]

Robert, here is a little Insite for ahead some day. A fully discharged battery voltage 11.90,
A full charge battery 12.70. A Diesel engine needs starter to spin the engine min 150 rpm's.
You are setting at 10 volts, yes the starter solenoid will click. Did you try and hold the bypass
switch, long with key switch and try to start engine. The information above I sent you, pretty
well fits in with low voltage. It may be possible you have a bad battery causing both battery's
to drain. Would suggest check all your connections at batteries, just one loose connection not
tighten up will case the above in no start. This happen more times than a person would think,
the reason with sliding battery tray pushing tray in to lock will move connection just a little
but causes problems. Dave Atherton Retired Cat Mechanic

[Bryan Beamon]

Robert suggest  you also check your battery isolator to make sure it is charging  both battery banks while hooked up to AC. We have a Big boy battery isolator with two positive cables, check each cable with your volt meter to ground and they should show the same voltage 13.5 approximately. Hope this helps.

[Robert Green]

Thanks Bryan and Dave. I used my battery charger and restored the new batteries to fully charged. Rig fired up with no problem. I had battery disconnects installed when I replaced all the batteries a few weeks ago. I had left the chassis batteries ON, but have now switched them to OFF. Hope this helps keep them from draining until I can sort out the charging matter. 

The coach batteries are all sitting full at 6 volts.

Greatly appreciate all the help and advice. Thanks!