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03 trailblazer remote start

Printed From: the12volt.com
Forum Name: Car Security and Convenience
Forum Discription: Car Alarms, Keyless Entries, Remote Starters, Immobilizer Bypasses, Sensors, Door Locks, Window Modules, Heated Mirrors, Heated Seats, etc.
URL: https://www.the12volt.com/installbay/forum_posts.asp?tid=110574
Printed Date: July 18, 2025 at 8:26 PM


Topic: 03 trailblazer remote start

Posted By: 96hawkcnvt
Subject: 03 trailblazer remote start
Date Posted: January 11, 2009 at 9:01 PM

Need some ideas. Installing a remote start in a 2003 Trailblazer and seemingly have a problem with the bypass module. Using a GMDLBP and it seems to be programming properly. Sometimes it won't even crank but most often it starts & runs for just a second & then quits. Have tried another GMDLBP module with the same result.

Tried with the key in & if turned to the ignition position it will remote start & run.

Can anyone tell me if the 2nd acc. (brown) is needed? Doesn't seem to matter if connected or not for this problem.

Thanks for any ideas.

Todd

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Replies:

Posted By: kgerry
Date Posted: January 12, 2009 at 11:59 AM
sounds like possibly a tach issue... Brown 2nd Acc is not required..... did you set it up for tach or voltage sense? did you power 2nd Ign???   if it runs fine when the key is turned to IGN then that basically eliminates a PL problem and says you aren't powering a needed Ign wire...... grab a meter and verify that your pink & white IGN wires are being properly powered......

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Kevin Gerry
Certified Electronics Technician
MECP First Class Installer

Owner/Installer
Classic Car Audio
since 1979




Posted By: matt87gta
Date Posted: January 12, 2009 at 12:11 PM

I am the installer for this particular vehicle for TrackTime Motorsports...  It is a 2003 Trailblazer LS.

The RS is the Scytek Astra 1000 2-Way and we are using the GMDLBP Bypasskit.

I have double and triple checked all the connections and everything seems to be fine.  All connections are soldered and secure.  I am using the tach mode with the tach feed wired tapped into pin 49 on the blue connector on the PCM under hood.  I have relearned the tach signal several times to attempt to rule that out.  Also attempted with and without the "Smart Start" engaged on the RS to no effect.  When it cranks and doesn't start, it goes through the three start attempts and then stops trying to start with the same condition each time - cranks, fires, then immediately dies.  I get none of the built in troubleshooting aids from the RS as far as lights flashing.  Inserting the key during RS operation and attempting to crank results in no cranking so Anti-Grind appears to be wired properly.

As Todd mentioned, as a troubleshooting step, I engaged the remote starter with the FOB, waited for it to attempt to start, which it did and cranked, fired, died...  and then I reached in and put the key in and turned the ignition to run and the next time the RS attempted to start, it started and stayed running.

I wired a relay to engage 12V to the second accessory but the same condition persists.

TIA for any ideas you might have.





Posted By: matt87gta
Date Posted: January 12, 2009 at 12:19 PM

kgerry wrote:

sounds like possibly a tach issue... Brown 2nd Acc is not required..... did you set it up for tach or voltage sense? did you power 2nd Ign???   if it runs fine when the key is turned to IGN then that basically eliminates a PL problem and says you aren't powering a needed Ign wire...... grab a meter and verify that your pink & white IGN wires are being properly powered......

Sorry about that, I didn't see yoru reply before I posted my initial reply...

But yes, I am using tach mode but have also tried tachless in all settings and none of them alter the condition.  This is in a heated garage (60* F) so cold start is not an issue.

Everything is wired per the instructions.  The relay pack is wired to both Ignitions (white and pink).  I did not double check 12V at both IGN 1 and 2 during RS operation but will do so.  I do know for certain that the Accessory 1 circuit is getting 12V during RS operation as I verified that before using it to trigger the additional relay for feeding Accessory 2 when I added that.





Posted By: matt87gta
Date Posted: January 12, 2009 at 1:10 PM

I am not so sure that it is not a PL issue...  From what I understand about PL, it will allow the engine to crank, fire, but without the proper lock cylinder password transmission on the serial data circuit from the BCM to the PCM, the engine will die quickly.  This sounds exactly like what I am seeing.

Also, I believe the times I have not had a successful starting attempt from the RS are due to attempting to start the engine more than 3 times without the proper PL code and thus triggering the 10 minute wait period built into the PL system.  Starting with the proper PL code (ie, the key) resets/erases the wait period.

Has anybody used this particular Bypass module on a TB with success?





Posted By: kgerry
Date Posted: January 12, 2009 at 1:14 PM

yes... many times

the R-code is generated during crank...  he stated he left the key in the IGN position and it starts fine... to me this would eliminate it being a Passlock issue and point to an IGN wire not being properly powered... as otherwise simply leaving the key in the IGN position would not correct a Passlock issue....



-------------
Kevin Gerry
Certified Electronics Technician
MECP First Class Installer

Owner/Installer
Classic Car Audio
since 1979




Posted By: matt87gta
Date Posted: January 12, 2009 at 1:23 PM

kgerry wrote:

yes... many times

Good to know, thanks.  I will verify 12V on both IGN 1 and IGN 2 and go from there.  I currently do not have the Accessory 2 wired to get 12V during RS operation...  I temporarily installed the additional relay lastnight but removed it when no change occurred.  I will leave that un-wired for now per your instructions.

I also have tried 2 different GMDLBP modules to verify I didn't just have a defective one without any change in the condition.

Question...  I am curious as to what the role in having the serial data circuit not connected to the GMDLBP module until all the other circuits are connected to it is?  There is an "Important" note in the instructions to connect it that way...





Posted By: matt87gta
Date Posted: January 12, 2009 at 1:26 PM
kgerry wrote:

the R-code is generated during crank...  he stated he left the key in the IGN position and it starts fine... to me this would eliminate it being a Passlock issue and point to an IGN wire not being properly powered... as otherwise simply leaving the key in the IGN position would not correct a Passlock issue....


Ahhh....  I see.  Makes sense.  I guess I know where to focus then :) .





Posted By: kgerry
Date Posted: January 12, 2009 at 1:59 PM
they recommend this to avoid a potential data collision on the class II bus... i have personally always hooked up all wires and just plugged in the module and have never had any issues.....

-------------
Kevin Gerry
Certified Electronics Technician
MECP First Class Installer

Owner/Installer
Classic Car Audio
since 1979




Posted By: matt87gta
Date Posted: January 13, 2009 at 7:24 PM
Thanks for the help again.  It indeed was a lack of 12V being transmitted to the IGN 2 circuit.  I had a bad relay and had to swap the relay pack out.  Everything is working perfectly.




Posted By: hpcustomsound
Date Posted: January 15, 2009 at 11:08 PM
Do Not use any other Bypass module  other then FORTIN   (INTSL) is the best  2 days ago I had a problem like that and it end up being the I DATA LINK BYPASS at first it wasnt controling the doors after it gave me problems of starting i had to borow one from a buddy at 8 oclock at night and it wasn't funny infront of the customer.




Posted By: OhioMike1101
Date Posted: January 16, 2009 at 8:43 AM

hpcustomsound wrote:

Do Not use any other Bypass module  other then FORTIN   (INTSL) is the best  2 days ago I had a problem like that and it end up being the I DATA LINK BYPASS at first it wasnt controling the doors after it gave me problems of starting i had to borow one from a buddy at 8 oclock at night and it wasn't funny infront of the customer.

I use the ads-dlslgm1 on those Trailblazers all the time and they work perfect every time.



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South Side Audio
2501 S. High St
Columbus, OH 43207




Posted By: kgerry
Date Posted: January 16, 2009 at 11:22 AM
i use Idata all the time as well with no issues....     

-------------
Kevin Gerry
Certified Electronics Technician
MECP First Class Installer

Owner/Installer
Classic Car Audio
since 1979





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