I replaced the oil pan gasket, valve cover casked on pass...

I replaced the oil pan gasket, valve cover casked on passenger side and both motor mounts on my 2007 [escalade esv](/topics-escalade-esv/) and now it won't start. Verified starter is good but car does nothing when turning ignition...

I replaced the oil pan gasket, valve cover casked on passenger side and both motor mounts on my 2007 [escalade esv](/topics-escalade-esv/) and now it won't start. Verified starter is good but car does nothing when turning ignition. It only has limited functionality when ignition is turned to power accessory on. Dash lights up but doesn't read gas level and shift/gear indicator not on. Radio, cigarette lighter, low beam headlights and climate control work but nothing else. Battery charged up (12.5V) and been on trickle charger. Seem that one of the control modules is not working properly. Hope I didn't smash the wiring harness from [engine](/topics-engine-cadillac/) to transmission when I lifted the engine with the hoist to change the motor mounts! Mechanic's Assistant: Have you checked the fuses? The dashboard bulbs? Yes I have checked all fuses inside drivers side of car and under hood. Dash bulbs were good before I worked on car Mechanic's Assistant: Are you fixing your Escalade ESV yourself? What have you tried so far? Yes, working on it myself... I have taken starter to auto parts store to get bench tested and it is good. Visually checked all wire connections to engine sensors that I was working on. I have charged battery and monitored voltage. I have scanned for codes and communication with mt hand held scanner. It read the vin & engine files fine. Has no fault codes.

Automotive Expert
Good afternoon Would you like a wiring diagram , you will need to check where you are losing power going to the starter
Automotive Expert
Take a look at this , keep in mind the starter fuse will only have power when cranking the engine

Ok, thanks. I will verify but it seems like an interlock not letting the car start when the ignition is cranked. The shift/gear indicator light is not on so it may not know it is in park.
Automotive Expert
It is very possible it can be from the car not thinking its in gear , the computer should send voltage on the yellow and black wire to the starter relay to close the circuit , if its not doing that , then we need to look at other things like the switch on the transmission .

I verified I have 12v on 87 of the starter relay.
Automotive Expert
is the starter fuse good ?

starter fuse is good. I don't get 12V on 86 of the starter relay when turning the ignition though.
Automotive Expert
If you have 12 volts on 87 the starter should be spinning and you would have 12 volts at the 40 amp starter fuse .

Ok, it was actually 30 that had 12v. Like it should but I verified not getting 12v to 87 with ignition turned.
Automotive Expert
I would try messing with the wires on the park neutral switch on the transmission and see if you can get the shifter to light up , i'll send you the diagram for it. If that was disconnected it may need to be replaced, i don't know why i have never plugged one back in and it worked

Ok, will do.
Automotive Expert
Good Luck , let me know if you need anything else

Ok, ill check the switch wires but I didn't touch anything there when I was working on it. I'll see if I can check continuity on wires from the TCM connection and the transmission side since I could have pinched the harness while I was changing the motor mounts. Not sure that would explain why so many other functions like [tail lights](/topics-tail-light-cadillac/), brake lights blinkers, dome lights, high beam lights etc are not working.
Automotive Expert
Here is the lighting diagram , it almost sounds like something is disconnected .

The only thing working in the BCM fuse panel seems to be the cooled seats. All fuses are good. Wondering if something more central is wrong like ECM? Is there a safe way to try to reset the ECM before I attempt troubleshooting any further?
Automotive Expert
Look at this , i would think its a fusible link

I did not find any issues with any of the relays or fuses in the underwood fuse compartment. All have 12v. Also, all the symptoms are not common to one module. How do I troubleshoot each module? Do you have pin outs?
Automotive Expert
The wiring diagrams all have numbers on the wires and if you look close enough at the connectors there will usually be the first and last numbers of the wires. Thats why i sent the power distribution diagram , you may possibly see them all receiving power from the same place

Ok, I will spend some time tracing wires today but I did notice if I remove the fuse for BCM, TCM or ECM the systems are the same as I have. No change. The radio, instrument cluster light up and a few other functions when the key is turned to accessory on but no shift indicator and no start when turning the ignition to start position. I can hear each module powered back on when the fuse is re-installed.
Automotive Expert
i would print off and study the power distribution and just start checking and crossing things off

Automotive Expert
Did you figure anything out ?

No comm from BCM. Had it towed to shop and they say the module needs to be replaced. Quote for $1000 for the part and then programming to VIN. They said it may have other issues but need to fix that first. I am considering ordering a remanufactured BCU pre programmed to my VIN for $195 to fix myself.
Automotive Expert
I would try the $195 one ,there are also places that you can send yours out to be repaired , i don't know which would be cheaper

Ok, thanks for the recommendation. I am thinking it's worth a try. I don't feel comfortable forking out $1000 plus programming fees to find out the root cause is a different module. $200 not so bad.
Automotive Expert
I feel the same way

Thanks for your help on this issue! Definitely isn't an easy fix like blown fuse or harness disconnected
Automotive Expert
Hopefully it will be easy as unplugging a module and plugging a new one in

Hoping so!
Automotive Expert
me too

What others are asking

Car stalling and jumping.
This car has a transmission that has solenoids that control the shifting and sometimes the solenoids or speed sensor causes erratic shifting. The vehicle would have to be tested to see what codes are in the computer and diagnose the...
Opinion on '90 to '95 Nissan Pathfinder
Not the new ones, but the old ones were good, yes. Nissan Pathfinders (https://www.yourmechanic.com/scheduled-maintenance/nissan-pathfinder) were decent vehicles, but you don't want to get one that is all worn out. Those have a lot of problems with automatic transmissions. If you...
Car won't start, and rear windshield wipers don't work
Most likely, these are two separate issues. A vehicle that doesn't crank or start indicates a problem in the starting/charging system. It may be that the battery connections (https://www.yourmechanic.com/services/service-battery-cables) didn't get tightened down properly at the time of replacement. The...
When slowing down, the engine stops
If you already took the vehicle to the dealer to have them look at it, then they would not have said they cannot find any problems, unless they cannot duplicate the problem. You may have an intermittent problem with something...
Message showing up on my dash board
Hi there. These lights are turning on because the computer is trying to control the vehicle because it detects a wheel that is slipping or has some instability. Most of the time, this is caused by a bad wheel speed...
Power capabilities
Hi there. The engine will not start to break down or lose power at that point. The factory engine does not make that much power on its own so I have to assume you are talking about aftermarket power modifications....
Can you drive on 3 lug nuts
Hey there, thanks for writing in. All of the lug nuts are necessary (https://www.yourmechanic.com/article/is-it-safe-to-drive-with-a-missing-lug-nut). Leaving even one off could result in warping of the brake rotors (https://www.yourmechanic.com/services/brake-rotor-disc-replacement) or drums (https://www.yourmechanic.com/services/brake-drum-replacement), necessitating their replacement. If two are left off that puts...
I got a new battery new alternator put in but my battery just gets drained I keep having to buy new batterys
This may be a sign of a failing voltage regulator or potentially a bad grounding problem causing a draw on the system. The voltage regulator is a unit that regulates the charging of the battery by the alternator. Often times...
Grand Cherokee 1999 Side Swiped Door Replacement Possibly.
My first recommendation would be to determine how many miles the vehicle has and memorize it. Then I would look over your vehicle and give it your honest opinion of its condition (assuming that the doors were fixed). Then I...