So, my radio is the culprit of a parasitic drain on the battery, drawing 5 - 6 amps. I removed the fuse to stop the drain. However, is there a way to resolve this? Several years ago, I did install the iSimple Bluetooth module. However, I do not believe that's the issue because I've had battery problems before then.

 

Is it a factory radio?

 

Is it the base radio, or Nav system in your vehicle.


Which fuse did you pull, the amp 30 A fuse in the engine compartment, or the Radio/Sband/VICS fuse in the passenger footwell?
If you pulled the Radio/S-Band/VICS fuse, then it is likely the VICS (Onstar module) that is the culprit.
remove all but the right hand connector from the Onstar Module, re-insert the fuse and see if this stops your parasitic draw.
If it does, then you will know it's the Onstar Module.
The dealer can reflash the module to eliminate the parasitic issue.
There is a pic of the VCIM connectors to remove in the attached PDF of known Parasitic draw locations.

 

I removed the 15 A under the passenger compartment. I do not have OnStar capability. I also did more testing and found that the radio is not the culprit. During shutoff, it'll stay at 5.5 amps for 5 minutes, then drop to 1.4 for a little bit. Then it'll shoot up to 10 amps for 1/4 of a second and then drop to 0.06 amps. Before the battery had died, I last drove the car this past Sunday. Battery is brand new too.

 

 

Ensure that all wiring related to the radio, including the iSimple Bluetooth module and any other accessories, is properly installed and not damaged. Look for any exposed or frayed wires that could be causing a short circuit.

 

Make sure to update the firmware on the I simple blue tooth to most current firmware, since it's most likely the problem. Hence will continue to try to blue tooth connect to a device to stay awake, even after the BCM has sent the sleep mode.

Short of that, need to know if stock radio, or not. If stock radio, may need be firmware updates, or radio just given up the ghost, and not accepting the sleep mode command from the BCM to fully go into sleep mode. Regarding after market radio, will not be the radio itself, but the after market adapter that may need to be firmware update, or the just not accepting the sleep mode command from the BCM. If running stereo amps, then double check the control wire off the amps, to where they where wired. The after market radio control wire is the better option since it will handle a higher amp load, then the after market control wire that you can fry the circuit wide open with too much amperage draw from it. Also double check the amps to make sure they are fully powering done once they stop receiving the voltage on the control wire.

One last thing, and that is possible that you have a module that low voltage glitch, and why it will not go into sleep mode. To solve this (hard reset of all modules), disconnect the battery cables, touch the cable together away from the battery, then reconnect the battery once is has been fully charged. If battery is old and will not pass a CCA test, then replace the battery and again, make sure to touch the battery cables together away from the battery, before you install the cables.
The down and dirty, modules need to see at least 12 volts, or they will low voltage glitch. With battery that will no longer pass a CCA test, when you go to start the car, starter is drawing a lot of amperage, which case the battery voltage to drop on a questionable battery way down, and the modules will low voltage glitch again.

To go further on this subject, with car running, BCM should be at 14.1~3 volts, with rest of the modules at around 14 volts (can check these with Tech II). if you find a module that is lower then this, then need to check is connector and ground wire for corrosion problems that is causing the low voltage problem in the first place. The power goes to the engine fuse box, to the BCM, then BCM out to the other modules in the car. As for voltage on the dash dial and DIC (should be 14.1 volts), that is not the voltage of the dash, but the voltage of the ECM that is getting it power from the BCM.
Quick break down,alternator sends out 14.7v to battery, battery should be at 14.5, BCM at 14.1~14.3, and then Ecm should be about .2V lower then BCM voltage at end of line (voltage drops from the wiring). If such is not the case, then time to start pulling connectors to clean them, to solve the voltage problems

 

@dperlich what was the resolution? I am having the EXACT same problem. Thinking about buying another radio and plugging it in to see if it resolves, can't find any issues visually

 

I no longer have the car. It threw a rod back in 2021 with 170,000 miles flat. I don't think I ever solved the problem. Honestly, the battery issue was the worst party shot Oregonian that car. I also had a module fail back in 2016 which bricked the entire car. I now drive a 2018 Sierra SLT and bought the wife a 2025 Kia Carnival - which has literally been the best vehicle I've ever had.

 

Its the I simple blue tooth module, since it will keep on searching even after the radio/it has been given the sleep mode command.
Best bet is to make sure its flashed with the latest firmware, and even then, still a problem that is continues to have by not going into sleep mode once the BCM has given it the sleep command..

 

I have the same issue. This is the original Navigation radio in a 2009 Z06. It has never been removed. I did swap the XM module for a GM Sirius module and added one of Rays iPad adapters back in 2009.
I can hear the Sirius module on the driver's wheel well clicking on/off. But unplugging the Sirius module does not stop the draw. Something in the main radio is not shutting down. I removed the 15-amp radio fuse in the passenger footwell and that stops the drain.

 

So I got another base radio today for $10, plugged it in and nothing changed. I then removed the i Simple bluetooth harness and module and it is still having a draw of 2.8ish amps. If I remove the fuse the same as @Vito.A then the draw goes away. I am thinking it has to be something in the harness then? I removed all the Onstar plugs and antenna and that had no change either. 06 Z51 with bose

 

I'm guessing there is a relay for the radio that is not shutting down properly. It also provides power to the other radio modules.