Starting Problem please Help

[cory0789]

I have a 1995 monarch signature motorhome. It has been sitting for about a year and I have replaced the ignition switch thinking it was the problem already. What happens is I turn the key to crank it and the gauges go to zero. The batteries are both good. I have already jumpered the solenoid to check it just to hear it and it works. No voltage gets to the small wire on the solenoid though. What else can I try, I have a feeling its something very simple but i cannot figure it out.

Thanks,

PS I do not have a wiring diagram so of someone has one that would be great also.

[mgscott4]

This is old school starter and solenoid testing.

With the key "on", I used to use an old screwdriver and touch the "hot" terminal to the solenoid terminal, You get a bunch of sparks and burn marks on the old screwdriver, but if the starter and solenoid are good, it will turn over and start, if the solenoid is bad it won't turn over and you may still get a click but if it doesn't turn over it is bad.

Hey, you asked what else you could try. At least you will know if your starter is good or not.

[TeJay]

This is a routine issue with a high current demanding devices like starters. Every and I mean EVERY battery cable connection must be good. When you are trying to create a path for 1/2 amp of current flow it's not a problem. When you are trying to pass 150-amps it is a problem. High current needs big cables with good connections. You've said that the battery is good. I don't know how you tested it but. Now when you energize the solenoid you should hear the solenoid go click. If you have a lose or high resistance connection things go dead. Check both positive and negative connections at both ends from the battery to the solenoid, then to the starter. My guess is that you'll find a loose or corroded connection.

Let me relate to you a true story that happened to me in my auto class. PROBLEM: Intermittent cranking issue on an old pickup. PREVIOUS WORK: New starter, new alternator three new batteries and still intermittent no start over a 3-5 month time period. Several shops looked at it and nobody fixed it. The Principal brought the truck to the auto shop. We were studying the cranking circuit at the time. I reviewed the circuit and then started the lab for the day. I sent two kids out and within 5 minutes they came back and it was fixed.

Now the $64,000 dollar question??? What did everybody else miss????

The negative battery cable which connects to the block down around the cylinder head and is the ground path for current flow was simply loose. They cleaned the area, installed a lock washer, tightened it and problem solved.

You may have some other issues but first and foremost you have to eliminate cable connections first.

TeJay

[DADSDOGHOUSE]

On my 1990 Signature L-10 I also had starting issues. Sometimes I had to try the key 10 or 12 turns and then The starter would only turn part of a turn and stop.
I pulled the 80lb starter out several times and had it tested at 3 shops. I replaced the large solenoid on the starter and still no change. Finally found a small Ford type solenoid on the front firewall wiring harness area that sounded odd. Replaced that and turns over and starts in1 or 2cycles every time. I replaced all the starter primary wiring prior to pulling the starter out, both positive and negative side as well as setting up 2 different grounds on the frame and engine block. Have some one turn the key while you listen under the front cap, should be able to hear it click when try's to energize and pass current back to starter sloenoid.

[DADSDOGHOUSE]

Forgot to mention the front small solenoid only passes the 12v trigger current to the large rear solenoid, it handles the 200 amps the starter needs to crank the engine over, so the front solenoid only has 12 guage wires to the large nuts on each side.

[cory0789]

I have tested the solenoid at tge starter by jumping across it already and it is good... As far as another small solenoid i dont know where it is or what it looks like. We havetightened and cleaned sll cable connections that we know of...

The small wire going to the big solenoid at the starter is getting no voltage when cranking.... What sends voltage to this wire?

[TeJay]

We also had another solenoid on our 1999 DS up and to the right of the radiator that was bad. Probably the best way is to physically follow the heavy wires. these MH manufacturers will put stuff in out of the way places and of course there's not schematics or pictures to let you know.

TeJay

[twinboat]

The power from the ignition switch goes to the neutral safety switch, then on to the start solenoid. Try starting in neutral.

[D Lindy]

x2 on TeJay's post, you've got in all likely hood a bad/corroded/loose primary ground off the batteries.

[deandec]

My rig has a starter solenoid and an ignition solenoid.

The ignition solenoid is mounted with the chassis fuse panel in the front driver side basement.

My ignition solenoid had a bad ground connection. Engine would not turn over. Batteries were good.

Of course, I first bought a new solenoid before checking the ground connection. So now have a new spare solenoid.

[D Lindy]

The KEY to CORY0798's problem is that he looses ALL dash gages etc when the key is turned to the START position. This means he has power to the dash UNTIL there is a big amp draw i.e. trying to engage the starter, then everything does dead - BAD GROUND.

[TeJay]

As stated in my original post. The symptoms described I've seen dozens and dozens of times. There has to be a bad connection somewhere in the circuit. He just has not located it just yet. If the batteries are good (That's a big IF) and all goes dead when he tries to crank it is a sure indication of not enough current getting through somewhere. SEARCH, SEARCH, SEARCH. Disconnect every possible connection and then look for more. Don't forget the NEGATIVE connections. Yes the bad connection could also be internal inside of a solenoid. You can't clean those internal contacts but you can replace the solenoid.

I heard about this the other day. Current flow and how it is utilized in today's highly evolved electronic systems has changed. Years ago it was common practice to use CHASSIS ground. That means that the chassis of a device (starter) used the body of the starter as a path to ground. Bolted to a metal body part then acted as the return path for the current flow. Many systems today don't rely on chassis grounds but actually have specific wires coming from an electrical device and leading to grounds.

WHY?? Well a lot today's systems use carbon fiber, plastic, etc and it's harder and harder to find a ground path for current flow. Even back in the 80's the computer systems controlled the ground side of a circuit instead of the positive side. Your throttle position sensor is just one example. The variable resistor controls the ground side of the 5-V going to the computer.

TeJay

[OLYLEN]

If you have a set of jumper cables. Go From chassis batteries GROUND to the frame then try start. If you start you have a ground problem. One EZ test that still may or may not work but might/could help with diagnosis.

LEN

[cory0789]

Update:::

I have replaced the starting solenoid on the back panel and it still did not work... I cleaned the ground off the starter to the chasis frame and still nothing... I tried putting jumper cable on negative battery side to chassis and nothing still...

Can someone explain what ground commections i need to check? What else i can do to find the bad ground?

Here is what i do know...

On the starting solenoid on back panel i get 12v to one side but when cranking it does not pass voltage to the other side... This is a new solenoid so its not that but what stops the current from going across...

I know the brown wire small goes to the neutral safety relay but i never get 12v to it either...