Glow plugs work first start only

[Atchuuu]

Glow plugs work every time after I disconnect the battery and hook them back up. I base this on the fact that the wait light blinks, voltage meter fluctuates and the fact that the truck starts right up.

however, once shut down, even if it is cold outside and the truck has not been started for a couple days, the only way to get the wait light and voltage fluctuations is to disconnect batteries.

Any thoughts? GP are new

 

[Mogman]

A couple things, the voltage should not fluctuate until the main timer has timed out, 8 seconds or so, then it goes into "after glow" where the EESS turns on and off the glow plugs to keep them warm for about a minuet or so, then they turn off.
If the wait light is just "blinking" and the EESS goes into afterglow it will start, especially if you wait 15 seconds or so as they will warm up but more slowly.

You need to go through the troubleshooting guide for the glow plugs, hopefully someone will post as I do not have them handy.

This is also why I have a light on one of the glow plugs to actually see what the glow plugs are doing, I do have one EESS box (I rotate them every time I service the truck) that at times will only go into afterglow but because I can see that I just wait 15 seconds or so and it starts right up.

Battery switches makes it easier too, as I do not have to even pull the seat to service my electrical system.

 

[MarkM]

Take baby steps. Check each plug (still in the engine) with a meter to see if they are still viable. If the plugs are good it is more than likely the box is having issues and is very common. Many of us keep a good spare box around just for these issues.

I put in a new set of plugs (PITA) only to find out they all burnt-out in two min because a relay in the box was stuck and kept power going to the plugs.

Remember the box and the glow plug temp unit on the block are a matched set as there have been many revisions to the glow plug system because of all the failures.

Mark

 

[Atchuuu]

If I use a battery kill switch it solves the problem of the wait light not flashing after the first start. Essentially it’s like disconnecting batteries each time. Are they any reasons that this is not an acceptable fix rather than a new box?

 

[Coug]

If I use a battery kill switch it solves the problem of the wait light not flashing after the first start. Essentially it’s like disconnecting batteries each time. Are they any reasons that this is not an acceptable fix rather than a new box?

I don't see why not. I've had a battery disconnect switch in my truck for 3 years now no issues
It's not so much a "fix" as a workaround. Who knows how long it will continue to work in this manor, and it could decide to stop working entirely in a matter of weeks, or might work for many years

 

[Retiredwarhorses]

Flashing wait light is a TSU…