Unhooked Battery, now it won't start- Please help! *SOLVED*

[Scrapman]

2007 LTZ- bought a liftgate actuator and was installing it. When I plugged in the new actuator, it starting whirring and making noise; so I thought I would unhook the negative battery cable. I finished installing the actuator and hooked the battery back up. Now it won't start. The lights, front windows and some dash lights work, but it will not start. No locks work, and my key fobs do not work. There is no "lock" staying on my dash, just an engine light and the traction light. Battery is showing 12.7 volts and I have checked all the fuses under the hood.

This has to be a simple fix. Please Help.

I even took the new actuator off, but it did not help.

Any ideas?

 

[wsteele]

2007 LTZ- bought a liftgate actuator and was installing it. When I plugged in the new actuator, it starting whirring and making noise; so I thought I would unhook the negative battery cable. I finished installing the actuator and hooked the battery back up. Now it won't start. The lights, front windows and some dash lights work, but it will not start. No locks work, and my key fobs do not work. There is no "lock" staying on my dash, just an engine light and the traction light. Battery is showing 12.7 volts and I have checked all the fuses under the hood.

This has to be a simple fix. Please Help.

I even took the new actuator off, but it did not help.

Any ideas?

Do you have a Tech 2 (or near someone in the Tech 2 owners sticky)?

 

[BG1988]

2007 LTZ- bought a liftgate actuator and was installing it. When I plugged in the new actuator, it starting whirring and making noise; so I thought I would unhook the negative battery cable. I finished installing the actuator and hooked the battery back up. Now it won't start. The lights, front windows and some dash lights work, but it will not start. No locks work, and my key fobs do not work. There is no "lock" staying on my dash, just an engine light and the traction light. Battery is showing 12.7 volts and I have checked all the fuses under the hood.

This has to be a simple fix. Please Help.

I even took the new actuator off, but it did not help.

Any ideas?

check the fuses you popped one of them most likely the BCM

THIS is why the battery should be always disconnected before any work is done on the SUV... Hopefully you did not damage it..

check the fuse box under the dash on the drivers side this is the HIGH POWER fuse box

 

[wsteele]

One thing I noticed in the shop manual is the power liftgate module is connected to the Theft Deterrent logic. You might check to see if you triggered the theft deterrent system.

A tech 2 would be really helpful I suspect.

 

[petethepug]

Longshot but have you tried starting it with a different key & fob?

 

[Scrapman]

Do you have a Tech 2 (or near someone in the Tech 2 owners sticky)?

No Tech 2, just a normal code reader. No codes shown

 

[wsteele]

No Tech 2, just a normal code reader. No codes shown

Looking at my shop manual, you may have fouled up the theft deterrent system. I have not done any research into how to unstick that system. You might what to do some research on that system and how to reset it. It will inhibit starting.

Edit: a brief scan of possible fixes to the theft deterrent system includes disconnecting the battery negative terminal again and leaving it disconnected for 20+ minutes. After 20+ minutes, reconnect.

The theory is after that, the key fobs should work, lock nd unlock the doors with the fob and then start the truck. I have no idea if that will work or not…

 

[Scrapman]

check the fuses you popped one of them most likely the BCM

THIS is why the battery should be always disconnected before any work is done on the SUV... Hopefully you did not damage it..

check the fuse box under the dash on the drivers side this is the HIGH POWER fuse box

Will do. I checked all the fuses under the hood, but not all the fuses in the cabin fuse box

 

[Scrapman]

Looking at my shop manual, you may have fouled up the theft deterrent system. I have not done any research into how to unstick that system. You might what to do some research on that system and how to reset it. It will inhibit starting.

Wouldn't the engine lockout light be lit on the cluster if the theft system locked me out? The lockout light isn't on.

 

[Doubeleive]

disconnect the battery again, touch the battery cables together for a few seconds, hook them back up, try to start again.

 

[Scrapman]

Longshot but have you tried starting it with a different key & fob?

Yep. Three different ones. None of the three fobs or keys work.

 

[Scrapman]

disconnect the battery again, touch the battery cables together for a few seconds, hook them back up, try to start again.

Tried this trick already. Didn't work.

 

[Doubeleive]

then disconnect the battery cables, leave them off, go put the key in the ignition and turn it to start a couple times, flip the headlight switch a couples times and step on the brake pedal a couple times, then hook the cables back up and try again.

 

[camaroz2887]

If the battery terminals are the only other connection you messed with, disconnect em for a few and re connect. When you put the negative terminal on do it quickly without moving it too much causing it to turn the car on and off quickly. The computers don’t like it much.

Can’t say it’s your issue for sure but I’ve had similar problems after disconnecting the battery for service.

2 people posted while I was typing this... at least it’s still active here.

 

[wsteele]

Wouldn't the engine lockout light be lit on the cluster if the theft system locked me out? The lockout light isn't on.

I have no idea. I assume there was no alarm, so maybe that lamp request wasn’t set.

A generic ODB reader won’t get the body codes or be able to program the lift gate control module (if that needs to be programmed).

Where do you live?

 

[Doubeleive]

and if that doesn't work then bang on the top of the underhood fuse box a few times and see if anything changes.
if it was just the security system glitching the door locks should still work, so that tells me you may have a bad connection somewhere, you might have to start checking other grounds.

 

[Doubeleive]

I have no idea. I assume there was no alarm, so maybe that lamp request wasn’t set.

A generic ODB reader won’t get the body codes or be able to program the lift gate control module (if that needs to be programmed).

Where do you live?

liftgate module doesn't need programming

 

[wsteele]

liftgate module doesn't need programming

Yeah, I am just going from the shop manual which discusses lift gate control module programming, I frankly haven’t even been in that part of the Tech 2, so have no idea what “programming it” means.

 

[Doubeleive]

Yeah, I am just going from the shop manual which discusses lift gate control module programming, I frankly haven’t even been in that part of the Tech 2, so have no idea what “programming it” means.

they may be referring to adjusting the height/landing (I think) if it didn't work properly after replacing it

 

[wsteele]

and if that doesn't work then bang on the top of the underhood fuse box a few times and see if anything changes.
if it was just the security system glitching the door locks should still work, so that tells me you may have a bad connection somewhere, you might have to start checking other grounds.

I think when the theft deterrent system disables the truck, the power locks are disabled as well, at least that is the way I remember it. I have never had it happen to me, so am just going on what I have read.