Glow plug controller clicking noise

[johnsp218]

Ok guys I have a weird one. My start box makes a clicking noise every 30 seconds. This happens with the truck just sitting there with nothing turned on, basically how you would leave it to park over night. Otherwise it starts fine with the wait light working properly. My old yellow label box stopped working so I pulled it and found the ground wires burnt. I replaced the burnt wires and reinstalled it. It then worked again but made this clicking noise. I then order a replacement box, installed it properly and its making the same noise. It's a real head scratcher, I checked the TM's and the internet but could'nt find anything. I do have good ground to the box. Thanks in advance for any advise.

 

[Wire Fox]

Is anything else cutting out at the same time you get the clicks? I'm wondering if you have your circuit breaker tripping and resetting over and over.

Honestly, your best diagnostic here is probably going using an ammeter on different circuits to try and figure out exactly what's toggling on and off. It really sounds like the power is getting switched on and off to your start controller which is why you're getting the relay clicks.

 

[johnsp218]

It's hard to say for everything is turned off. I used a stethoscope to determine that the click is coming from the start box and I was not aware that the start box receives power while the ignition is in the off position.

 

[johnsp218]

So I got her figured out today and thanks everyone for your help and input. Turns out I actually had wires in the harness that were shorting out. I didn't notice that some army mechanic had stripped the insulation from the major large wires in the bundle and the crimped splices were touching. Some heat srink and electrical tape did the trick. All is perfect now... dodged a bullet on this one.