Community Forums

Jestan · 10-07-2016, 10:55 AM

When in start position, I have no power at the solenoid to engage the starter.

If I tag 12v to the solenoid post, it will start.

I believe the wire goes to neutral switch on transmission then to ignition switch.

can anyone tell me how to trace the wire or solve the problem?

This is a 2005 40' Alpine.

twinboat · 10-07-2016, 11:25 AM

There is probably another solenoid in the circuit. The ignition switch, thru the neutral safety controls that.

That solenoid switches the higher power from the batteries, to the starter mounted solenoid. That slave solenoid will be somewhere between the batteries and engine.

deandec · 10-11-2016, 12:36 PM

On my rig there is an "ignition solenoid" that controls the chassis fuses activated by the ignition switch.

That solenoid is located at the chassis fuse board.

I discovered that the ground had failed. Installed a new ground wire and location and off we sent.

Skip426 · 10-11-2016, 12:49 PM

Quote:

Originally Posted by Jestan

If I tag 12v to the solenoid post, it will start.
I believe the wire goes to neutral switch on transmission then to ignition switch.
This is a 2005 40' Alpine.

Your starter system will have a second relay ( solenoid ) in the heavy gauge wire that runs to the solenoid on the starter, that your powering up to work the starter.
The second relay , gets its ground from the transmission control module , when the transmission is in neutral, and gets the low amp 12 volt power from the ignition switch, and provides high amp 12 volt power to the solenoid on the starter. This second relay is usually between the chassis batteries and the starter, and because it's part of the chassis wiring could be mounted to the frame.
This photo is a common type of starter relay ( solenoid). Your's may not be identical , but has the same function.

Jestan · 10-18-2016, 07:12 AM

Thanks. can you tell me where the wire goes from the solenoid?

Jestan · 10-18-2016, 07:16 AM

Quote:

Originally Posted by Jestan

When in start position, I have no power at the solenoid to engage the starter.

If I tag 12v to the solenoid post, it will start.

I believe the wire goes to neutral switch on transmission then to ignition switch.

can anyone tell me how to trace the wire or solve the problem?

This is a 2005 40' Alpine.

Can you tell me where the neutral switch is located?

Skip426 · 10-18-2016, 09:23 AM

The starter relay gets power directly from the battery , on one side (one of the larger post) and the other side goes directly to the starter solenoid.
I've replaced the starter relay twice, in 7 years in my coach.

The neutral sense function , is internal in the transmission controller; however there may be a fuse, or another smaller relay, in the circuit, between the controller and the starter relay.

Look around the engine compartment , for a 5 inch square box, about 3 inches high, with 3 or 4 wiring multiple connectors into it's sides.
Right hand side of the photo below.
Second photo , shows cover removed, these are from my Freightliner chassis.
Third photo is a similar , box from a Spartan chassis with Cummins engine.

Skip426 · 10-18-2016, 09:39 AM

Here's another photo showing my main starter relay, mounted on a plate, on the frame between the batteries and the starter; visible only from under the coach; before I changed it the first time . Red arrow. The other two items are 135 amp fuses to protect the 30' run of cable from the batteries ( coach and chassis ) to the front of the coach.

Old Scout · 10-18-2016, 09:56 AM

All good input but none are from Alpine owners. The secondary starter solenoid for the 05 Alpine is on the backside of the rear bulkhead [not frame side] in the battery compartment [said another way--on the front bulkhead in the compartment were the air filter is located]. The solenoid is a std., continuous use solenoid, similar to what is pictured above. Starter and main solenoid are powered full-time thru large bat cables from the battery compartment. The secondary solenoid has two larger wires [10/12 gauge] coming from the bats and going to the main solenoid; and two smaller wired--one is a ground, the other comes from the ignition key switch in the cab. The secondary solenoid is subject to failure but you need to verify that feed wire from ignition switch is providing power in the start position. The ignition key switch is also subject to failure [owners often hang lots of junk on their key rings--not good for ignition switches].

Jestan · 10-23-2016, 11:38 AM

Quote:

Originally Posted by Old Scout

All good input but none are from Alpine owners. The secondary starter solenoid for the 05 Alpine is on the backside of the rear bulkhead [not frame side] in the battery compartment [said another way--on the front bulkhead in the compartment were the air filter is located]. The solenoid is a std., continuous use solenoid, similar to what is pictured above. Starter and main solenoid are powered full-time thru large bat cables from the battery compartment. The secondary solenoid has two larger wires [10/12 gauge] coming from the bats and going to the main solenoid; and two smaller wired--one is a ground, the other comes from the ignition key switch in the cab. The secondary solenoid is subject to failure but you need to verify that feed wire from ignition switch is providing power in the start position. The ignition key switch is also subject to failure [owners often hang lots of junk on their key rings--not good for ignition switches].

Thanks Old Scout. Solenoid is okay. I am not getting 12 v to the solenoid which comes from the ignition to activate the solenoid. I believe the switch is fed by the neutral start relay located in the transmission VM. I am looking for tbe physical of that relay and/or transmission VM.

Any ideas?

Jestan · 10-23-2016, 11:42 AM

Quote:

Originally Posted by Skip426

The starter relay gets power directly from the battery , on one side (one of the larger post) and the other side goes directly to the starter solenoid.
I've replaced the starter relay twice, in 7 years in my coach.

The neutral sense function , is internal in the transmission controller; however there may be a fuse, or another smaller relay, in the circuit, between the controller and the starter relay.

Look around the engine compartment , for a 5 inch square box, about 3 inches high, with 3 or 4 wiring multiple connectors into it's sides.
Right hand side of the photo below.
Second photo , shows cover removed, these are from my Freightliner chassis.
Third photo is a similar , box from a Spartan chassis with Cummins engine.

Thank you. I do not seem to have that black box in my Alpine. I have the fuse box but no neutral start relay

Old Scout · 10-23-2016, 02:13 PM

Ok--before you get all excited trying to find a "black box" based on input from some other brand of coach, recommend you confirm you are getting power from the start position on the ignition switch. Ignition switch failure is a fairly common problem with your era of coach......
PS--less common but possible--the Allison shift display panel or the Allison tranny ECM may have failed. My shift display recently failed so no neutral sensing for ignition. If shift panel failure, no gear selection display on panel.