Starter solenoid 8.3 Cummins/Freightliner

[dmcb]

I have no power to the starter solenoid. I have replaced the switch but that wasn't the problem. The solenoid on the starter works OK and I have rigged a switch to the battery to start the rig. I am told there is a second solenoid that the switch triggers which In turn triggers the one on the starter.

I cannot find that solenoid if it indeed does exist. Sure could use some help as I have to go to the battery compartment each time I start.

Thank you in advance

Doug

[bobsallyh]

dcmb, you would probably get more response by moving this to the HDT forum section, although I'm sure someone who is on the HDT forum will see this post.

[Darryl&Rita]

Too hard to troubleshoot via keyboard. You need to start chasing wires. Shotgunning parts at it is going to get expensive, fast. Your neighborhood Freightliner dealer should be able to get a wiring diagram for your specific truck, or get you access to the database, then start following wires.

[Kirk W]

5 hours ago, dmcb said:

I am told there is a second solenoid that the switch triggers which In turn triggers the one on the starter.

While I am not experienced with the chassis that you have, a relay that is operated by the ignition switch to supply power to the starter solenoid is not an uncommon thing. You should be able to locate it by tracing the heavy power cable back from the solenoid toward the battery to find it.  It should look something like this.

                                          

Here is a link to a Freightliner Diesel Engine Starter Troubleshooting Guide.

[Ronbo]

I have a kenworth with a Cummins n14. I have a relay on the dash that I removed and connected a push button start switch on the dash. I think the actual problem is a switch on the transmission. If you think it will help I can take some pics tomorrow. It is in storage right now.

[dmcb]

Should have mentioned it is on an Allegro 40' Bus. I tried following the wire but it goes in a group of wires shielded. Without cutting everything away it is impossible to trace.

Kirk, thanks for the pic. There are several solenoids under there and It is difficult to know what they all do. I'll dig deeper.

It started with once in a while I had to hit the switch 2 or 3 times before it would turn the starter. Then one day nothing.

I had thought of a push button to start and it might come to that. I really am not throwing parts without thought. I didn't know there were 2 solenoids. I determined the one on the starter was good. Talking to Freightliner about this, they didn't tell me about the second solenoid and after all the tests I did, they said it had to be the ignition switch. Well it wasn't then someone told me about the second solenoid. I ran a wire from the battery through a switch to the starter solenoid to get started. That works well except I have to go outside to the battery to start. Sure beats sitting along the road tho. 

Also should have mentioned it is a 2002 model. All the fuses are good.

[Lance A Lott]

With a long run you probably have a small wire going from the switch to the presumed solenoid or relay then to the starter solenoid. Have you tryed a helper to activate the switch well you search, often a relay will still click but not carry juice. You can always run a wire from the switch your self. Have you checked to make sure the switch is getting power and is sending it out to the starter? I had one that would run all the excessorys but not the start position. Although it sound like a relay. A second relay would probably not be a Cummins item but an Allegro part.

[Kirk W]

Since the coach is from Tiffin, try contacting them as they might be able to help. Some things could have been relocated on the chassis in coach construction so they may know where to look. 

[Wrknrvr]

 You need to purchase a https://www.googleadservices.com/pagead/aclk?sa=L&ai=DChcSEwiG9p792angAhVkGH0KHf2BBboYABAJGgJwdg&ohost=www.google.com&cid=CAASE-Ro3N03GcpwAD5176WQgf6zM1E&sig=AOD64_2kij5r5JNzYsOnJtxnI3WoPF7qhg&ctype=5&q=&ved=2ahUKEwjpnpr92angAhWL_p8KHcbbBvIQwg96BAgHEA8&adurl=

 

 But before you purchase one, do some reading as to how it works. It should trace that wire directly to the problem.

 

 It has saved me a lot of time in my repair business. 

 

 Just a thought,.  Vern

[Scrap]

In 2002 the "mag switch" was usually a plastic bodied Cole Hersee, (now Littelfuse) switch.  Gonna look like:  

 

[dmcb]

Thanks again. I have a few days if other things to do but will try some things mentioned here. I think this is all Freightliner because Tiffin buys it ready to do. Even the dash is installed. I don't have much faith in Freightliner. They told me the part number I needed. I found it to be an obsolete item but found one at a dealer in Nevada. Cost $100. Not even close to the right part. Right one was about $30.

Doug 

[lenp]

dmcb, 

I too, have problems starting the rig, intermittently though.  Tough trying to figure it out when it only happens occasionally.

The wiring diagrams from Sparton (I know your on a Freighliner but perhaps wiring is similar) show multiple relays/solenoids in the starter "path".  One is controlled by the Allison to lockout the starter if not in neutral.  You really need to get a wiring diagram and start tracing wires (and I need to do the same!).

Friend with an older Allegro with starting issues had to replace the Allison touch pad to correct his start problem.  Was not cheap!

Good luck and let us know if you solve the problem.

Lenp

[Wrknrvr]

  Sorry for my other post. As it was incorrect for what I was trying to post.

 

 This should be  the tool you need.    

  I did try to copy a picture from Home Depit of the  unit that I use for tracing a single wire. But this forum would not let me post it. Although my other post did have a picture of it.

 With that tool up you can remove one end of the wire, hook the tone generator to it and follow that where ever it goes without taking walls apart or clusters of wires.

 

 Let's see if this gives you a better idea how a tone generator works.

   I hope this helps with finding someone's problem.

 

   I can be confusing at times getting my point across.

 

 

  Vern