Grid heater relay and killer grid heater bolt revisited

[Turbo Terry]

Sorry to start another thread on this. Did a search and read all that but my Indy that serviced my truck brought it up the other day so here goes. When I got the recall on the relay I disconnected the 10 m bolt to the relay so I could park in the garage. Now I have a new relay from the recall and it’s connected back up. So does the bad old replaced relay stick shut causing the grounding bolt to melt causing the killer grid bolt issue or I’m I missing something here. I really don’t need the grid heater here most time. Truck is started in warm garage. And is hot until it comes back. If it got -20 f and I had to leave it outside I would reconnect the grid heater and take a chance. I need some input on this. Thanks

 

[sag2]

Correct, it sticks on and melts the relay or wiring potentially starting a fire, or melts the bolt inside the intake. I suppose a fire is worse than the bolt melting off.

 

[Turbo Terry]

So just disc it at the battery let it set a code and a check engine light and carry a 10 m socket to be able to reconnect if I get get stuck out at -40 f somewhere check the grid bolt for looseness and drive on that’s the answer for me then over and done

 

[Turbo Terry]

I noticed that the killer bolt has some pretty heavy black plastic (Bakelite ) ? Under it. Very thick. With the dash gauge on battery voltage you can see the grid heater suck the voltage down from 14 volts to 11,5 then it recovers . I can only imagine the heat if the relay sticks on with two battery’s to power it. 200 plus amps is like welding amps WOW no wonder it melts that tiny bolt

 

[Ozymandias]

Why do you think they issued a recall and changed the relay?
To make it burn nicer with sparkling stars?

 

[Turbo Terry]

So the big question is can you trust the new recalled relay to shut off after the original bump of 200 plus amps or not. I guess watch the voltage gauge on start up is a must or just disconnect it and keep it for real cold starts and that’s it. Banks kits are most of a thousand dollars and another almost thousand for a Indy install. Too old to do it myself anymore. But I can’t just begin to think of trashing a motor over this. Stupid. Then there’s the warranty god help us all

 

[petersonj]

I think if I owned one of these trucks, I would figure out how to wire in a momentary switch inside the cab to operate the grid heaters when necessary and be done with it. I did this with my '02 when it was new. The switch hardly gets used, but when it is needed I use it prior to starting the engine. I then start the engine and that's it - no post-cycling grid heaters. Way less wear and tear on relays, the grid heater, and the alternator. It has probably greatly contributed to the fact that I have never needed to replace the alternator, grid heaters, or grid heater relays at over 380,000 miles.

- John

 

[Turbo Terry]

Ozy your so funny

 

[Turbo Terry]

I have thought of that already. I was thinking under the hood right off the battery. Would have to be pretty heavy for 200 plus amps. A knife blade but no more that I would use it a 10 m wrench and a headlamp will be fine .

 

[Ozymandias]

You are over thinking it, once again. These relays have been around for decades in our trucks and worked just fine. Now it seems they had a batch of bad ones that weren't up to the task and are replaced by working ones. Why not just relax now.

 

[petersonj]

I have thought of that already. I was thinking under the hood right off the battery. Would have to be pretty heavy for 200 plus amps.

I am not talking about replacing the relay with high amperage relays or knife switch. I talking about using the existing relay / relays, but tapping into the very low amperage coils that operate the relay/ relays. I personally have not seen the coil on the later model Cummins, but I am fairly certain the coil only uses about 150 milliamps of current maximum. That means light gauge wiring into the cab and a light duty momentary switch.

- John

 

[Turbo Terry]

I think you might have something there. Go for it.

 

[Turbo Terry]

Ozy when you get a 2007 or newer truck with these issues tell me that again I will listen to you until then I’m not sure

 

[Turbo Terry]

Oh and I still like you carry on

 

[Timd32]

I would not be too worried about the new relay.

Being in NJ, what I've done is just not use the remote start, and bypass the cycle on start up.

It's actually an electronic relay, not an old school mechanical device.

From the recall:

REASON FOR THIS SAFETY RECALL Some of the above vehicles can experience an engine compartment fire originating from the Generation 1 solid state intake air grid heater relay. An electrical short in the relay can potentially lead to a vehicle fire with the ignition on or off. A vehicle fire can result in increased risk of occupant injury and/or injury to persons outside the vehicle, as well as property damage.

Here are some pics off Genos for a 2018 and earlier.

Similar to even the 12V dual mechanical relays. different layout of the terminals but to me it's similar enough to any old school starter or plow solenoid.

Then here is the newer one. Off ebay, the new part number is different this is the recalled one in the pic off ebay.

New part number
68606435AB

 

[Turbo Terry]

When I just jump ? In right and hit the brake pedal and button it still cycles the grid heaters but rather quickly and starts up. Even with a hot truck. This is at 35 f outside. If I would leave truck outside all night at say zero I really think it would need the grid heaters to start . They get pretty stiff. If I lived up in Fairbanks 40 below and other places in Alaska I would not have a diesel truck. A gasser with a manuel would be my choice . Being in the warm garage and plugging it in for a couple hours if left out is the secret. My old 99 5,9always started but was sure stiff a few times anyway I understand all this much better than I did before and want to thank everyone for their input

 

[Turbo Terry]

I’m currently looking at a continuous 12v 300 amp on off switch to put off the passenger battery in front of the grid heater so all I have to do is open the hood and turn it off and on when I need it or don’t.Instead of taking the nut off and on the battery stud etc. I think I have found one

 

[Signal73]

2020 down use the old school relay. They switched to the troublesome electronic relay for 2021.

 

[Signal73]

I’m currently looking at a continuous 12v 300 amp on off switch to put off the passenger battery in front of the grid heater so all I have to do is open the hood and turn it off and on when I need it or don’t.Instead of taking the nut off and on the battery stud etc. I think I have found one

I used one of these for my winch power lead. It’s mounted on the PDC on the driver side. May be overkill but will handle the load for sure.

https://www.flamingriver.com/battery-disconnect-switches/fr1048-500-amp-big-switch-for-racing

 

[SSchang]

2020 down use the old school relay. They switched to the troublesome electronic relay for 2021.

My 2020 had a recall for the relay.