Christobevii3

iTrader: (1)

I am swapping a 2004 5.3L chevy truck motor into my 4.3L 2001 s10 blazer 2dr. I had the wiring harness and computer done at current performance in florida. I put power to the car to load the custom tune that was done for my car and get a security light afterwards that is constant.

I am told that he removed the vats system and to look elsewhere. What else could be giving me a constant security light even with the keys out? The starter isn't even kicking over which he said the security thing wouldn't keep from doing.

Any help is appreciated or ideas to try, thanks

andrew69_04

iTrader: (148)

grounds? something not hooked up? i bet u missed something somewhere. maybe ur harness got messed up when they worked it over?

Jaysz28

iTrader: (19)

I'm wondering if your vats is in the BCM, rather than the PCM. Start by bypass the vats in the truck. When I had my issue, I found the vats relay, and jumped it with a paperclip. Then I could at least get the car to crank.

Ended up being a ground that was removed when I made the harness. Ran a ground to the diagnostic port, and walla, everything worked

good luck

-jason

busta9876

iTrader: (3)

anti-theft system is in the BCM, the BCM sends a signal the PCM (via serial data) telling it to enable injectors. When VATS is removed from the PCM, it simply allows the PCM to run without the signal from the BCM. You're security indicator is controled by the BCM.

Looking at schematics, the BCM does not control the starter relay , so it should crank over reguardless of the security indicator being on.

check under hood fuse block fuse IGN C 20amp
also check IGN A 40amp

Might mess with shifter too, park neutral switch will keep it from starting if in wrong position.

good luck

01WS6/tamu

iTrader: (37)

Need to scan the BCM with a tech 2 and see what code it has in it. You might also try locking and unlocking the door with the keyless entry if you have it. The lamp can also be related to the content theft if you have keyless. The indicator goes solid when you lock it with the door open using the door switch and then starts blinking once you close the door which enables the content theft. Same way if you use the transmitter.

Christobevii3

iTrader: (1)

I don't have keyless entry, i'll go poke around tomorrow. Thanks for the hints, keep them coming so I can have more ideas.

andrew69_04

iTrader: (148)

ya my light came on solid this morning when i locked my truck with door open. idk if a security light would effect cranking though. Stupid question, but have you tried unhooking the battery for a bit?

01WS6/tamu

iTrader: (37)

Then it has a hard fault with the passlock need to scan the pcm it may have a code present. For sure the BCM will have a hard fault set scan it and go from there.

Christobevii3

iTrader: (1)

Yeah I've left the battery off overnight each time i'm not working on it. Guessing I got to tow it to the dealer to get the bcm scanned?

Christobevii3

iTrader: (1)

Ok just talked to the GM dealership after they did a tech 2 computer scan. They are saying the BCM and Main computer aren't talking at all. I paid current performance for my computer to be programmed and a wiring harness.

Am I wrong that I expected this to be part of it or am I suppose to pay $75 an hour now to hope someone can link something up at the dealership?

This is what current performance said to me when I first asked and they are now closed till the 10th...

This is after when I ordered the harness in january/february last year that i'd have it by mid march and the harness didn't show up for a couple weeks after the end of march (kinda sucks when you have school and have to leave your car at your parents to go back to college...).

IOwnCalculus

Out of morbid curiosity, what are you trying to do other than turn the light off? If you've got a no-crank you've got issues elsewhere, VATS will still et it crank.

Christobevii3

iTrader: (1)

So it should still be able to crank with a solid security light even without the key in and the bcm not talking at all?

01WS6/tamu

iTrader: (37)

yes ^

01WS6/tamu

iTrader: (37)

what dtc's does it have stored

IOwnCalculus

Yep. If it was a VATS problem it would crank, fire, then stall almost immediately.

Most LS1 swaps into older vehicles forgo the BCM altogether - mine doesn't have nor need one. The engine computer doesn't really get involved in the cranking process much either, as far as I know (but I haven't ever really looked too closely at that side of the wiring diagram). I would just start working through your wiring. The harness for the 5.3 should be expecting +12V for cranking somewhere - my bet is wherever that is hooked up to isn't getting +12V.

01WS6/tamu

iTrader: (37)

If your blazer does not have the floor shift then it will have a park neutral switch on the side of the transmission. Do you have the wires installed and the switch adjusted correctly. IF it has a park neutral switch it will have a digital PRNDL display on the instrument cluster.

Christobevii3

iTrader: (1)

yes it is on the side and column shifter and I'm thinking this is where i'm at. I kicked the starter over by jumpering it with a wire and it went fine so it is getting power there. I switched the relay out in the fuse box for a good one and checked the fuses. So I'm guessing it has to be an adjustment with the park switch.

The gears show up fine on the dash except i can't go into 1st, is there a guide on how to adjust this? It is a new one because the old one was damaged btw

Thanks for all the help.

ja_engineer

Could it be the ignition switch, when mine went out I had problems getting it to crank because it wasn't getting enough voltage.

01WS6/tamu

iTrader: (37)

Shift the trans all of the way to first. Then loosen the two bolts on the side holding the Pn switch and tweak it back and forth until the one indicator lights up on the cluster.

busta9876

iTrader: (3)

check back to my post on 12/20 has schematic of park/neu switch....you could check for power at the relay to see if park/neutral switch is causing you're problem.

You should check the circuit one leg at a time untill you find you're problem.

1. Looking at the schematics, IGN 0 fuse feeds ignition switch 12v+ HOT AT ALL TIMES

2. When swith is in START position, the ignition switch feeds 12v+ to the CRANK fuse located in the underhood fuse block.

3. From the CRANK fuse power is routed to pin E (purple wire) on the park/neutral safty switch connector. When the safty switch is in park or neutral, 12v+ should be seen on pin G (purple with white stripe) The connector with these pins should be Gray in color, the other one is white. (I think, check the pin locations and wire color to confirm)

4. From park neutral safty switch pin G power will flow to the starter relay.

Now, pull the starter relay and look for the schematic printed on the side of the relay.
When 12v+ and Ground is supplied to 85 & 86, the relay will trip. Polarity does not matter on the relay. Notice 85 & 86 will be on opposit corners, this is so it does not matter which way you turn the relay around.

Look where 85 & 86 is, and then notice where those pins are when you plug in the relay into the fuse block. CHECK this locations IN the fuse block for GROUND and 12v+ while key is in CRANK position. If you have ground & power that part is fine.

You can jumper the other two pins IN the fuse block and that should kick in the starter. Be careful. One of the other two pins goes to a 40 amp fuse IGN A, other side goes to the starter solenoid (heavy gauge purple wire)

hope this helps...