Power Drainage

[Nate Peters]

My truck battery is constantly dying. I performed a parasitic draw test and turns out the radio and backup lamp. When i remove the fuse for the radio and reverse lights the power draw goes down to zero.

I know that fixing the problem with the radio is to just get a new radio. What can i do about the constant power usage by the reverse lights? (are reverse lights and backup lights the same thing?)

[The Zip]

Don't know whats causing the drain, but reverse and backup lights are the same just as tail lights and park lights are the same.

[Roger Lalonde]

I have a 2007-8 Silverado that has a battery going dead dead dead overnight. The dome light does not even come on. The vehicle has been to a dealership many times. The problem is intermittent and occasional. When the problem appears the draw is 3.5 amps. When testing begins the problem goes away and might not return for weeks. I have since installed a second battery and installed a solenoid to boost the battery to start. When the problem appears it might be present for weeks and again when testing starts the problem disappears. I want to sell the vehicle but cannot pass this problem on to the next person. Can you please help me solve this problem? Roger.

[Doug_Scott]

My truck battery is constantly dying. I performed a parasitic draw test and turns out the radio and backup lamp. When i remove the fuse for the radio and reverse lights the power draw goes down to zero.

I know that fixing the problem with the radio is to just get a new radio. What can i do about the constant power usage by the reverse lights? (are reverse lights and backup lights the same thing?)

 

From what I can find about the 2003 GMC Sierra, backup lights and radio are different fuses. If your truck happens to have BOSE, that has its own fuse as well. There will always be some parasitic draw, what is more important is what the amperage is. You can use an ammeter between the positive (or negative) cable and the post on the battery. Obviously this means you need to disconnect that terminal. You can also use a 12v test light for this test. Disconnect negative battery cable, and then connect the test light connector to the battery and use the probe to connect to the cable. If the light comes on, then there is a enough parasitic draw to kill the battery overnight.

 

Your truck should have the "Retained Accessory Power" feature. This is supposed to protect the battery from being drained by one of the accessories. Generally it will turn off all accessories after 10 min, provided you do not open a door. First thing I would try is next time you get home, shut the truck off, remove the key, and sit there listening to the radio. See if it shuts off after 10 minutes. 10 minutes is almost a lifetime if you just sit there and stare at the dash, so browse the internet on your cell phone while you wait. If the radio turns off after 10 minutes that means the RAP system is working. If it does not turn off, then you have found the issue. Now you need to find a troubleshooting guide for repairing RAP.

[Nate Peters]

 

From what I can find about the 2003 GMC Sierra, backup lights and radio are different fuses. If your truck happens to have BOSE, that has its own fuse as well. There will always be some parasitic draw, what is more important is what the amperage is. You can use an ammeter between the positive (or negative) cable and the post on the battery. Obviously this means you need to disconnect that terminal. You can also use a 12v test light for this test. Disconnect negative battery cable, and then connect the test light connector to the battery and use the probe to connect to the cable. If the light comes on, then there is a enough parasitic draw to kill the battery overnight.

 

Your truck should have the "Retained Accessory Power" feature. This is supposed to protect the battery from being drained by one of the accessories. Generally it will turn off all accessories after 10 min, provided you do not open a door. First thing I would try is next time you get home, shut the truck off, remove the key, and sit there listening to the radio. See if it shuts off after 10 minutes. 10 minutes is almost a lifetime if you just sit there and stare at the dash, so browse the internet on your cell phone while you wait. If the radio turns off after 10 minutes that means the RAP system is working. If it does not turn off, then you have found the issue. Now you need to find a troubleshooting guide for repairing RAP.

This actually helped a lot. Thanks so much.