TCM Related Parasitic Draw?

[kaedenr]

Hey there.

Wanted to run this by the forum and see if anyone had any pointers or experience with a similar issue. My truck has had a intermittent parasitic draw for the last several months now. It's a limited with the air ride that I put a level kit on, and didn't notice the issue until after I installed the level kit, so I originally assumed the issue lied with the air suspension somewhere, however now I think it's completely unrelated. It's also worth noting that I've noticed an electrical whine/hum that can be heard from underneath the truck that continues for hours after the truck is shut off. This, clearly, indicated to me that something is staying on/awake long after the truck is shut off, however the noise isn't always there after every time the truck is shut off, leading to an intermittent issue. The noise and draw issue however are becoming more frequent. Battery has been dead almost every morning for the last week or so.

So I finally took the time today to start checking amperage draw at the fuses in the TIPM with the truck shut off, and found fuse 24, which is the battery positive supply for the TCM, is drawing 2.5A long after the truck is shut off. Conveniently enough, when you pull the fuse, the electrical whine/hum noise stops. If you then put the fuse back in, the electrical noise does not come back until the key is cycled. Once the key is cycled and returned to the off position, the electrical noise then continues again, until the fuse is pulled.

With this information in mind, this leads me to believe that something has failed within the TCM that is causing the module to stay "awake" and therefore drain the battery. Initially thought this could be a TIPM issue because I know they're not necessarily known for their reliability, but to me now, it really sounds like a TCM issue. Really just checking to see if anyone else had any experience with something similar, or seems to think I'm on the right track here.. local dealer wants $1300 for a TCM at wholesale rate.. yikes.

 

[Jimmy07]

Hey there.

Wanted to run this by the forum and see if anyone had any pointers or experience with a similar issue. My truck has had a intermittent parasitic draw for the last several months now. It's a limited with the air ride that I put a level kit on, and didn't notice the issue until after I installed the level kit, so I originally assumed the issue lied with the air suspension somewhere, however now I think it's completely unrelated. It's also worth noting that I've noticed an electrical whine/hum that can be heard from underneath the truck that continues for hours after the truck is shut off. This, clearly, indicated to me that something is staying on/awake long after the truck is shut off, however the noise isn't always there after every time the truck is shut off, leading to an intermittent issue. The noise and draw issue however are becoming more frequent. Battery has been dead almost every morning for the last week or so.

So I finally took the time today to start checking amperage draw at the fuses in the TIPM with the truck shut off, and found fuse 24, which is the battery positive supply for the TCM, is drawing 2.5A long after the truck is shut off. Conveniently enough, when you pull the fuse, the electrical whine/hum noise stops. If you then put the fuse back in, the electrical noise does not come back until the key is cycled. Once the key is cycled and returned to the off position, the electrical noise then continues again, until the fuse is pulled.

With this information in mind, this leads me to believe that something has failed within the TCM that is causing the module to stay "awake" and therefore drain the battery. Initially thought this could be a TIPM issue because I know they're not necessarily known for their reliability, but to me now, it really sounds like a TCM issue. Really just checking to see if anyone else had any experience with something similar, or seems to think I'm on the right track here.. local dealer wants $1300 for a TCM at wholesale rate.. yikes.

Does this truck have etorque? Any faults stored in the TCM?

 

[kapinallinen2]

Hey there.

Wanted to run this by the forum and see if anyone had any pointers or experience with a similar issue. My truck has had a intermittent parasitic draw for the last several months now. It's a limited with the air ride that I put a level kit on, and didn't notice the issue until after I installed the level kit, so I originally assumed the issue lied with the air suspension somewhere, however now I think it's completely unrelated. It's also worth noting that I've noticed an electrical whine/hum that can be heard from underneath the truck that continues for hours after the truck is shut off. This, clearly, indicated to me that something is staying on/awake long after the truck is shut off, however the noise isn't always there after every time the truck is shut off, leading to an intermittent issue. The noise and draw issue however are becoming more frequent. Battery has been dead almost every morning for the last week or so.

So I finally took the time today to start checking amperage draw at the fuses in the TIPM with the truck shut off, and found fuse 24, which is the battery positive supply for the TCM, is drawing 2.5A long after the truck is shut off. Conveniently enough, when you pull the fuse, the electrical whine/hum noise stops. If you then put the fuse back in, the electrical noise does not come back until the key is cycled. Once the key is cycled and returned to the off position, the electrical noise then continues again, until the fuse is pulled.

With this information in mind, this leads me to believe that something has failed within the TCM that is causing the module to stay "awake" and therefore drain the battery. Initially thought this could be a TIPM issue because I know they're not necessarily known for their reliability, but to me now, it really sounds like a TCM issue. Really just checking to see if anyone else had any experience with something similar, or seems to think I'm on the right track here.. local dealer wants $1300 for a TCM at wholesale rate.. yikes.

Does not sound like there is a hard failure in the TCM, if there was, then the parasitic draw should return when you put the fuse back in? Could be that the module is not commanded to shut down, yes I realize that this does not help you much.
My problem of parasitic draw of several amps was caused by minor oxidation of a ground connection, this wreaked havoc with comms between modules.