03 Marquis no start

[William Jordan]

On my 03 Marquis Its a  Allison 4000MH and just for extra info the Trans ECU is a WT3ECU910A Off my Spec sheet in the Bath Medicine cabinet door

[william harrison]

 I disconnected the signal wire from the start relay and using a signal sniffer I traced it to the bundle of wires inside the shift column, then separately
traced the  start wire from the ignition switch, no  connection (as expected)
one wire is labeled 232 and the other 232a.  I could find no connection between either wire and the Allison shift control box where I was told the neutral safety relay is located. I have installed a rear start pushbutton
but still want to solve the original problem.

[Edward Buker]

William,

When you say you disconnected the wire from the start relay, do you mean the starter solenoid ? When you say you found the other end in the bundle in the shift column, what exactly are you referring to? Are you saying that you have continuity from the starter solenoid up to the touch panel area where the Allison control panel is located?

Later Ed

[william harrison]

 There is a solenoid in the coach battery compartment that connects to the starter Bendix.  The solenoid is energized by
a "start" signal that comes from a wire located in a bundle of wires that pass through the "shifter column" where the touch panel
shift control is located.  It does not connect to the ignition switch.  Supposedly the "start signal" comes from a connection made
between the ignition start wire via the neutral safety relay in the vim.  I could not find a connection between the start
signal and the vim.

[Edward Buker]

William,

I think I understand better....so you know that the relay in the rear works going to the starter Bendix and you have temporarily created a start button back there. You know that you have a path from the shift panel area to the rear relay.

It would seem the next steps are to apply 12 V to the wire that comes into the shift panel area and convince yourself that the wiring path from the shift panel area to the Bendix through the relay works. if it does then I think that you need to next verify what wire at the ignition switch is energized in the "crank" position and trace where that wire goes and verify that it is applying 12V where it is terminated.

I am not sure if you have contacted Monaco and or BCS to see where this relay is that enables the start sequence based on the shift pad gear position. It would be logical that it is in the shift pad area but you never know for sure. So basically verify the operation from the shift pad area back to the starter and then work from the ignition switch back to the shift pad area tracing the wire code and voltage.

Later Ed

[Steve Huber Co-Admin]

William,
Ignition Power comes from the shifter panel via wire #250. You can verify if it has power at CB27 in the electrical bay beneath the driver's seat.
If you haven't already, you may want to take a look at the Marquis elec. wiring diagrams in the Coach Assist section of the Members Only board.
Steve

[Steve Huber Co-Admin]

William,

I did some checking of the 03 Marquis wiring diagrams. Wires 232 and 232A enter the VIM via C42 pins 2&3 respectively. Both are labeled “Start” in the diagrams. 232 goes to the ignition key solenoid and ties into the Firewall Harness Connector C1 Pin 2 and runs back to pin 2 on C51, the Engine harness interface. From C51, 232 goes directly to the starter solenoid.
I was unable to trace 232A any farther but suspect it tells the VIM when the engine has started.
I found no fuses in the circuit, which leads me to suspect that one of the 2(?) fuses in the shifter console may be the culprit. See the below referenced thread for a description of the fuse locations.

This thread describes a problem similar to yours. David did a lot of troubleshooting but located all the fuses.
http://beaveramb.org/forum/index.php/topic,2701.msg20869.html#msg20869

Hope this helps some.
Steve

[william harrison]

 I noted that I replaced the "start" solenoid with an aftermarket one and found that the original one was good.
At that time the shift panel lit up and I could start it using a jumper on the start solenoid.  In the process of
re-installing the start solenoid I accidentally grounded the hot side of the solenoid momentarily and now the
shift panel is dark.  Yeah, I know I should have disconnected the battery lead.

[Steve Huber Co-Admin]

William,
It will not start if the shift panel is not powered. Check the fuses under the panel in the driver's console.
Steve

[william harrison]

 It does start Steve.  Where is the fuse panel again?  I see what looks like a cutout on top of the dashboard
but no fuses visible under the dash.

[william harrison]

 I can start it only by using the rear start switch I installed.  Just saw a schematic of the fuse and relay block located in the chassis battery compartment and it shows an output to the vim. Is this where vim power comes from?

[Steve Huber Co-Admin]

William,
The fuse I'm referring to is an automotive type fuse located under the transmission gear selector pad just to the left of the driver. You'll have to remove the side panel(s) to gain access.
Steve

[william harrison]

I still have a blank shifter panel.  I checked the fuses inside the VIM and they are ok.
 I left the start signal and ground open on the start solenoid and checked
for secondary fuses and found none except for the fuse tray on the wall of the battery box where a beaver schematic shows the source of a wire labeled VIM
power but does not indicate which fuse.  I suspect these are thermal activated
fuses. On the circuit board inside the VIM I have 12v on pins 6,7,8 and 16
reading from top to bottom.

[Steve Huber Co-Admin]

William,
Out of ideas as I don't have a schematic of the VIM itself. If you haven't yet, suggest you download and reference the "2003 Patriot Thunder Schematics Marquis, and other models 98 – 2003 Mixed". It's located in the Members Only Coach Assist section and has the best quality prints I could locate. You may also want to call BCS to see if they have a wiring diagram of  the VIM itself or any ideas.
Good Luck, Steve

[william harrison]

 Everything is fixed.  Problem(s) turned out to be located in the fuse panel in the engine battery compartment.  A corroded contact on the ecm relay and a blown 20amp fuse that powers the vim.  Thanks to all who responded.

Ps I purchases a wtec3 Allison manual and will make it available to all if I
can figure out how to do so.