Grid heater disconnect

[CooperJohn]

I have a 2008 truck and living in California, I decided to disconnect the positive cable at the battery to the solenoid that operates the grid heater after a friend of mine experienced engine problems after inhaling some slag from the nut connection. I read to start the truck immediately to avoid trouble codes and that worked for awhile but now I'm getting the p2609 code every time I start the truck even after clearing the code with an Edge insight. Is there a better way to disconnect the power to avoid trouble codes? Thanks!

 

[Mikey-KE7LBB]

Hook the cable back up to the relay and disconnect the power lead that feeds the heater itself. The ECM needs to see the relay get activated to keep everything happy... No codes this way.

 

[CooperJohn]

I'll give that a shot. Thanks!

 

[MichaelOverfield]

What Mikey said, that worked for me until I eliminated it and put in my new custom set up. Just be sure to well insulate that lug so you do not get it shorted to ground, because that will cause a fire for sure!

 

[tommyturbo]

Hook the cable back up to the relay and disconnect the power lead that feeds the heater itself. The ECM needs to see the relay get activated to keep everything happy... No codes this way.

Mikey. One time on a cold morning the fusible link melted at the relay ang threw the code. Since then,
I bought a replacement cable but didn't install it because of the learned threat of that bolt melting
issue. I have been starting quickly when the wait to start light does come on to avoid the code.
After reading your remedy, I reinstalled the new fusible link to the relay and then disconnected
the relay to heater cable and the results were the same. Code came back. Maybe I did not follow
your method correctly. That cable is actually not energized and cannot ground out or even spark
on any ground. Can you explain a little better how you achieved the grid heater not energizing and
not throwing codes.
Thanks in advance,
Tommyturbo

 

[Mikey-KE7LBB]

I only unhooked the wire that goes to the actual heater, and left the other three hooked up.

 

[tommyturbo]

I only unhooked the wire that goes to the actual heater, and left the other three hooked up. View attachment 134119

Mikey. I checked your set up and it looks the same as you described the first time. When you say no codes,
is that when you start quickly after the wait to start dash lite comes on or no code when starting after the
grid heater cycles out and the wait to start lite goes out. I get no code if starting before the heater circuit
cycles and get a code if I start after the lite goes out.
Tommyturbo

 

[Mikey-KE7LBB]

Either way works for me. You should check the condition of the small wires. The only time I ever got a code was when one got squished while replacing shocks. I fixed it with a butt connector, and haven't had an issue since. Perhaps your relay is bad, and that's the reason the fuse link needed replaced. All the ECM needs to see to be happy is the relay getting triggered.

 

[Topzide]

Is there any type of metal that a bolt could be made out of that wouldn't cause this? You'd think that Cummin's would not want that to ruin there reputation due to a $0.50 part! Any idea what current bolt is made of?

 

[sag2]

Either way works for me. You should check the condition of the small wires. The only time I ever got a code was when one got squished while replacing shocks. I fixed it with a butt connector, and haven't had an issue since. Perhaps your relay is bad, and that's the reason the fuse link needed replaced. All the ECM needs to see to be happy is the relay getting triggered.

This does not work with the newer trucks. The ECM looks for the electrical load from the heater and sets a code if the relay turns on but high current is not detected by the IBS.

 

[Topzide]

@sag2,If it is looking for a load, couldn't you rig a high power resistor or incandescent lamp like KC High Lighter to provided current draw without throwing a code? Just a thought for those who would want to disconnect the grid heater. You'd think that a solution would've been found other than pulling intake to inspect bolt for issues! Would be nice to be able to convert to the heater that Banks put in their RAM Horn!

 

[sag2]

I suppose you could find a load that would keep the ECM happy. The problem is it is going to create lots of heat. See Issue 115 page 96 for some additional info on grid heater disconnect. Also something to think about would be to source the Banks grid heater and drill and tap the intake horn to accept it. Swap the wire from OEM to Banks heater and problem may be solved. The only consideration might be if the grid heater relay sticks on anyway, and it melts the Banks heater too.

 

[Topzide]

STANDARD MOTOR PRODUCTS DIH4 {8972519740, 97251974} Info
Category: Air Intake Heater



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$43.79
From www.rockauto.com

 

[sag2]

Just ordered one.

 

[sag2]

OK, the heater showed up today. It pulls 43 amps, so it might require two to keep the ECM happy. Unfortunately I can't test it until the weather cools. Trying to fool the coolant temp sensor might work, but will probably result in rationality codes for the remaining sensors. It's 104° today.

 

[Topzide]

@sag2, Would the ECM see the current since it goes through a relay? The ECM will see the trigger to relay unless there's a monitor circuit built into the system somewhere. Would it see this through the battery current sensor? Just trying to get a heads up about changing the heater setup. Do you know if the threads are 22mm x 1.5? That's what I saw listed somewhere but can't find now. Looking forward to see what you come up with and if it would be a good mod for our trucks.

 

[sag2]

The current draw is measured by the intelligent battery sensor. I suppose even without the battery sensor it could look at voltage drop and make a close calculation of the current. The only way to test it is to get the truck cold enough to make the heater come on. I will check the threads today.

 

[Topzide]

@sag2, Kinda of what I thought was the process. I guess with the temps you're dealing with, it would take a truck load of ice to get grid heater to fire up. Thanks for the info you're providing the rest of us.

 

[sag2]

The threads measure 21.7mm x 1.5, so I guess that is 22 x 1.5. It uses a taper seat like some spark plugs.

 

[tommyturbo]

Either way works for me. You should check the condition of the small wires. The only time I ever got a code was when one got squished while replacing shocks. I fixed it with a butt connector, and haven't had an issue since. Perhaps your relay is bad, and that's the reason the fuse link needed replaced. All the ECM needs to see to be happy is the relay getting triggered.

Mikey. I changed out the relay and still get the check lite. The only wire disconnected is the one to the grid. I was reading that all that
needs connecting to the relay is the two thinner pop on wires only. That doesn't work either. I guess I will continue to start quickly after
ignition is on during colder mornings to prevent the check engine lite from coming on.
Tommyturbo