Originally Posted by UnregisteredUser

I'd guess that there's a pulley alignment problem there. Do you see more wear on one outer edge of the belt than on the other? Or, on the underside of the belt, more erosion of one side of the ribs than the other?

Originally Posted by dbbd1

I was thinking tensioner. The pulley (bearing) may "feel" okay but what about the spring tension from the tensioner?

Originally Posted by UnregisteredUser

Okay, with that it's clear that your jumper is powering up the transmission solenoid assembly, and that's the cause of the CEL and at least some of your drain.

So now the question is why, technically, you've got to use a jumper instead of a relay. Got a multimeter or at least a test light handy? We need to find out which signal is missing from the socket's relay coil terminals.

Looking at the relay socket from the left (driver's side) of the vehicle, there are three terminals oriented perpendicular to your shoulders, straight toward and straight away from you. Pin 85 is the rightmost, pin 86 the leftmost. When the engine is running we want to see power on pin 86, and ground (more or less zero volts) on pin 85. (Edited to add: You may have to have the engine running and transmission shifted into a drive gear to get the ground signal on pin 85. I'm not certain about this, so if you happen to find that it's always present when the engine is running, or not present until the transmission is shifted into gear, please let me know, and thanks!) If you've got a test lamp, just hang it between those two pins and it should light up when the engine is running and go dark when the engine stops. If a voltmeter, probe those terminals with negative to 85 and positive to 86, and start the engine. You should see something approximating battery voltage appearing there.

But it probably won't. In that case, if all you've got is a test light, hook the alligator clip to the battery positive terminal, probe to pin 85, and then start the engine (and shift into a drive gear, too). If the test lamp illuminates, pin 85's getting the right stuff. Then move the alligator clip to ground, and the probe to pin 86. Again, the lamp should illuminate when the engine runs (and in gear/not in gear doesn't matter for this test). If you're using a voltmeter instead, the first test is positive to battery positive, negative to pin 85, and the second test is positive to pin 86 and negative to chassis ground. In both you'd expect battery voltage or thereabouts to appear.

One of these two tests, though, should fail. If neither does, then grin all the way to the auto parts store because the problem was a failed relay all along.

With the knowledge of which test fails, we can proceed to figure out if it's a broken conductor or a failed driver in the PCM. Rather than write it all out, though, I'm going to be lazy and wait for you to tell me which path we need to investigate.

Originally Posted by UnregisteredUser

Excellent! We'll just go from there and see where it takes us. If it's the worst case scenario, I have a potential hack in mind that might be fun to try. Since it ain't my truck that gets blowed up if my hack is destructive.



Back before I got lazy I made my living coercing electrons.



I'd guess that there's a pulley alignment problem there. Do you see more wear on one outer edge of the belt than on the other? Or, on the underside of the belt, more erosion of one side of the ribs than the other?

Originally Posted by Moparite

Neither, This problem was on another forum I'm on and you need to take off the glaze on the pulleys. Mine does it too. Take off the serp belt and go over all the pulleys with a wire brush. That should do the trick.

Originally Posted by bunker

doing amp draw test, with the tranny relay in theres no drain. with relay jumped get 1.2 amp draw.