I’m new to the forums and would appreciate any help. Just purchased a 2001 Ram 2500. It has a mild case of previous owner syndrome that I’m trying to correct. Most of the wiring issues have been pretty straightforward but there’s one in the engine bay that I need some advise on. It appears that the Org\Blk leaving the ECM has been tied directly to ground, effectively eliminating intake air heater relay 2. Anyone venture a guess on why someone would do this? 
 

here’s a pic of the wire. https://imgur.com/BtAmNmw

No idea. that's a direct short for that ECM circuit.  No codes?  What happens when it's connected to the #2 solenoid?

Thanks for the reply. So I double checked the wiring diagram and it’s actually coming from the PCM not the ECM. It’s the TCC solenoid.  Had no codes and no noticeable issues. Decided to cut it and see what happens. When I pulled the wire out from under the air box it has what looks like a ferrite coil. Some sort of noise reduction modification. I’m researching this now. I reconnected it in the meantime. 

This is it. https://www.thoroughbreddiesel.com/1300030/?gclid=Cj0KCQjwuJz3BRDTARIsAMg-HxUgdJKiwzaKd8K7NGq76q2vU9-eweBK3B2BLjy_0bCpM0ZUFC8F03UaAlg4EALw_wcB

The truck transmission was experiencing the torque convertor lock/unlock problem  and that part was thought to fix it.  The real problem is high ac voltage from the alternator caused by leaking diodes in the rectifier.  The high AC noise can and will cause failure of the ABS, PCM, and ECM control modules.

1. Delete that wire;  all it is doing is covering over a problem and not correcting it.  
2. With a good multimeter, like a Fluke, measure the AC voltage at the b+ terminal on the back of the alternator engine at idle and all electrical turned off a good reading is 0.03 volts or less. 0.03-0.05 volts is marginal and 0.05+ volts is trouble waiting to happen.
3. Do what we like to call the W-T modification.  See below.
4. Retest the charging system for drop in AC voltage.

    

 

19 hours ago, IBMobile said:

The truck transmission was experiencing the torque convertor lock/unlock problem  and that part was thought to fix it.  The real problem is high ac voltage from the alternator caused by leaking diodes in the rectifier.  The high AC noise can and will cause failure of the ABS, PCM, and ECM control modules.

1. Delete that wire;  all it is doing is covering over a problem and not correcting it.  
2. With a good multimeter, like a Fluke, measure the AC voltage at the b+ terminal on the back of the alternator engine at idle and all electrical turned off a good reading is 0.03 volts or less. 0.03-0.05 volts is marginal and 0.05+ volts is trouble waiting to happen.
3. Do what we like to call the W-T modification.  See below.
4. Retest the charging system for drop in AC voltage.

    

 

Thanks! Seems easy enough. I appreciate the info. 

Used a fluke 199C scope meter and measured a very noisy 300mVAC. Seems insanely high. Went ahead with the W-T mod but it ended up turning into a complete wire job. Found some very shoddy work to include a wire wrapped in tin foil hahaha. So a reworked the entire charging system and grounds. The only problem was when I went to remove the trigger wire from the starter the post rotated and broke the wire internally. I have a Denso in order but I’m going to try to repair the old starter tomorrow. Here’s some pics from the job. 
 https://imgur.com/a/I2h1Wl8

Thanks for sharing the pics!!

 

What battery post adapters are those?  I like them.

 

The tinfoil thing was a "repair" they tried for the automatics to quit the "surging" (TC lock/unlock) that was being experienced about 10 to 12 years ago. 

 

Hag

The battery terminals are military style made by Quick Cable. I found them on eBay but Grainger also carries them. 
 

I laughed a little about the tinfoil. I still haven’t been able to start her up yet and see what the AC ripple looks like. I wasn’t able to repair that starter. The solenoid coil is shot. 

New denso starter installed. W-T mod and complete charge system rewiring complete. Fired right up. This is what I’m seeing off the B+ with the ground on the alternator chassis. 46mVAC with the occasional 57mVAC when something kicks on. 

Installed a nations alternator. Looking at 50mVAC off the B+ and 20mVAC at the battery. Gonna keep monitoring it and see if I see any symptoms of excessive noise.