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deandec · 06-03-2014, 07:27 PM

Hello, just back from a quick 5 day trip.

I shut the bus down and can restart the engine but no power to the transmission pad and other gauges surrounding same.

All my fuses light up, if working. There are three rows of fuses in the front basement compartment. The center row will not light up when the ignition switch is turned to on or when the engine is running. One of these fuses guards the transmission selector.

So ignition starts the engine but we cannot shift the Allison MD3060 transmission. We are stuck in a poor situation.

The power on the wire connections at a doodad which feeds the dead fuses is only 3.0vdc. I suspect it should be 12vdc.

Doodad:

Can you tell me what the doodad is called and where to find a replacement? It appears to provide the negative cable to the dead fuses.

deandec · 06-03-2014, 08:48 PM

Well, I got the thing out and it is a White Rodgers 80A 12vdc solenoid.

I can find it online at Grainger etc. but would like to source it locally to get the rig moved without towing. Any ideas you have on who might stock the item in the Sacramento area would be helpful.

In the meantime, what problems would I create by just omitting the solenoid from the circuit and joining the negative cables that pass through it?

I would disconnect the connection at arrival in a safe location.

deandec · 06-03-2014, 11:35 PM

Well, the problems with bypassing the ignition solenoid were no fuel shutdown solenoid function and another row of chassis fuses not working.

The positives were I got the row of fuses containing the transmission shifter powered up.

So after wiring open the shutdown solenoid so as to start the engine, I was able to cautiously move the rig to a safer spot.

I also proved to myself that the solenoid was the problem.

All's well that ends well.

Now to get that replacement solenoid.

dons2346 · 06-04-2014, 08:54 AM

Nothing special about the solenoid, any good auto parts store will have one

TQ60 · 06-04-2014, 09:12 AM

Wrong...

It looks like a ford type start relay...

Smells like a ford relay and if a ford relay is used itvwill smell after some time just before it blows out...

The auto parts store sell start relay which is intermittent duty so it does not like to stay on for longer than seconds.

You need to find one rated for continous duty.

Auto parts store may have one but confirm duty cycle.

In a jamb the auto one will work to get you moved.

phays · 06-04-2014, 07:48 PM

I just replaced my White Rodgers 80 amp, insulated coil, solenoid with a Phillips 80 amp. The other day, I couldn't shut the engine off. I had to use the kill switch in the engine compartment. I turned off the chassis batteries and pounded on the solenoid with a large pair of pliers. It began working again but since then I've replaced the Phillips solenoid with a Cole-Hersee 24213, 200 amp solenoid. I haven't started the engine yet but turning on the key lights up the transmission pad and all of the center fuse lights in the front run board.

The worst part of replacing the solenoid is re-attaching the wires on the positive side of the relay contacts. I found that if I attached those wires before mounting the solenoid to the back plate of the FRB it was easier.

deandec · 06-05-2014, 11:24 AM

Well I bench tested the solenoid and it clicks and introduces continuity to the main connectors. I do have a new one coming today.

I put the old one back into the rig, and I still cannot get the center row of fuses to light up. These affect the transmission shifter pad among other things.

In addition, the other chassis battery driven row of fuses now go dark when the key is turned on and when the engine is running. They are not important fuses for travel, but I still cannot drive the rig because the tranny shifter is not powered.

But.....if I power the center fuse row by connecting to the incoming side of the ignition solenoid I do get power to all three rows of my fuses and then can drive the vehicle. That way no key switch is needed for transmission shift function.

So, does anyone hazard a guess as to source of problem....Ignition Switch or Ignition solenoid??

TQ60 · 06-05-2014, 06:41 PM

Get your voltmeter and start checking voltages.

If ign then likely goes back to key via long route...

deandec · 06-05-2014, 07:40 PM

Ignition solenoid, to ECM, to ignition combo module, to key switch.

Replaced the ignition solenoid and same symptoms. Oh Well.......

dons2346 · 06-05-2014, 10:45 PM

Quote:

Originally Posted by TQ60

Wrong...

It looks like a ford type start relay...

Smells like a ford relay and if a ford relay is used itvwill smell after some .............

I said "good" auto parts store not referring to the local Manny, Moe&Jack type stores. They are available in auto parts stores, trust me.

chboone · 06-05-2014, 11:06 PM

NAPA should have a continuous duty relay. Being you only have 3 volts at the relay, may have a loose or corroded connection on the wire leading to the relay.

Chuck

deandec · 06-05-2014, 11:24 PM

Zorro, Inc delivered the replacement solenoid in about 36 hours via UPS and twenty bucks cheaper than Grainger.

But......that ignition solenoid preformed like the 19 year old one. No change.

I bypassed the solenoid and got all the chassis battery fuses operational for the trip to our storage yard. Not a convenient method but it worked.

Still searching, plus have a call in to Country Coach for Tech assistance.

YC1 · 06-06-2014, 01:59 AM

You really need to take a couple of voltage measurements. I don't think the solenoid is the issue.

Since you bench tested it you know you need 12 volts on one of the small terminals and ground on the other and that it clicks when engaged. Before that, measure the voltage on each large terminal.

If you see battery voltage of 12.5 or so on one large terminal and 0 on the other that is a good start. Then engage the solenoid. If you now see the 3 volts on each of the large terminals then you have a bad supply connection on the side that had the 12.5 volts to start. This supply connection could be close by or all the way to the battery. Don't wiggle and jiggle, take measurements to know you have found the issue.

It would be rare to have a solenoid in this setup switching ground. What is probably happening is once you engage the solenoid the loads pull the voltage low due to a resistance via a bad connection or burned wire. Most likely a simple loose nut.

To answer your question about bypassing a solenoid. In a pinch it is just fine. However in this pinch I doubt it is the issue.

phays · 06-06-2014, 07:07 AM

Similar to YC1's response, the same voltage problem can occur at the coil leads. I think the coil is about 15 ohms. It only takes a connection with a resistance of about 45 ohms to result in the voltage drop you see. As with all motor home 12 volt electrical problems, check the ground to the coil lead.