Battery light is on

You have no clue, guessing won't fix it , having wiring diagrams an using a DVOM - digital volt ohmmeter will. Testing an reading how they are suppose to work will. factory service info.

Turn Lamps
Battery positive voltage (B+) is supplied at all times to the turn signal/hazard flasher module in the hazard switch assembly from the rear fuse block T/SIG HAZ Fuse. The turn signal/hazard flasher module is permanently grounded. Battery positive voltage (B+) is supplied with the ignition switch in the ON or START position to the turn signal switch in the instrument panel from the rear fuse block IGN 1 Fuse.
When the turn signal switch is placed in the position to indicate a LH turn battery positive voltage (B+) is input to the turn signal/hazard flasher module Left Turn Input. In response to this input the turn signal/hazard flasher module supplies battery positive voltage (B+) in an on and off flashing pattern to the LH turn lamps and the instrument panel cluster (IPC) LH Turn Input. The LH turn lamps are permanently grounded so the LH turn lamps light when they have power, ground and turn off while power is removed. The IPC will also light the LH turn indicator.
When the turn signal switch is placed in the position to indicate a RH turn battery positive voltage (B+) is input to the turn signal/hazard flasher module Right Turn Input. In response to this input the turn signal/hazard flasher module supplies battery positive voltage (B+) in an on and off flashing pattern to the RH turn lamps and the IPC RH Turn Input. The RH turn lamps are permanently grounded so the RH turn lamps light when they have power and ground and turn off while power is removed. The IPC will also light the RH turn indicator.

Did the turn lamps operate properly?
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Go to Step 3
Go to Turn Signal Lamps and Indicators Inoperative - One Side
3
Disconnect the instrument panel cluster (IPC) connector.
Connect a test lamp between the inoperative turn signal input circuit at the IPC connector and a good ground.
Turn ON the ignition, with the engine OFF.
Move the turn signal switch to the inoperative turn position.
Does the test lamp turn ON and OFF with the turn signal lamps?


You people need to quit trying to play auto mechanic , you have no clue about automotive electrical circuits .

Service Information
2002 Buick Park Avenue ' Park Avenue (VIN C) Service Manual ' Body and Accessories ' Lighting Systems ' Description and Operation ' Document ID: 643323


Turn Signal/Cornering Lamps
The HZDT/SIG fuse in the fuse block - underhood - left supplies battery positive voltage to the turn signal/hazard flasher module and have ground at G202. The turn signal lamps may only be activated with the ignition switch in the ON or ACCY position. The T/SIG fuse in the fuse block - underhood - left supplies battery positive voltage to the turn signal switch. When the turn signal switch is placed in either the left or right position, current flow is from the turn signal switch assembly to the turn signal/hazard flasher module. The turn signal/hazard flasher module then sends an on-off voltage signal to either the left or right turn signals and their instrument cluster (IPC) indicator. When the hazard switch is pressed, all the turn signal lamps will flash including both IPC turn signal indicators. The left turn signals have ground at G106, G400 and at G402. The right turn signals have ground at G105 and G400. The turn signal switch supplies battery positive voltage to the cornering lamps, the left cornering lamp has ground at G105 and the right cornering lamp has ground at G106.











2002 Buick Park Avenue ' Park Avenue (VIN C) Service Manual ' Body and Accessories ' Lighting Systems ' Description and Operation ' Document ID: 643323

reset the computer throw diagnostic port .

Sounds like you lost the ground to the rear lights.

First thing you need to inspect the battery.The battery warning light is coming,due to battery is low on charge or battery got weak.If the battery is low on charge then get it recharged.But if battery is very old,then get it replaced.The battery and turn signal problem are two different problems.
Turn signals not working are due to faulty hazard switch/Turn signal switch,or faulty flasher unit.But in some cases its due to faulty turn signal fuse located in the interior fuse panel.This possibilities needs to be checked.Keep updated for further help.Thanks.Helpmech.

I suspect there is a problem with the turn signal/ hazard switch. turn the turn signal on left or right, if it doesn't flash, grip the hazard button and gently wiggle it around, if the signals start flashing, replace the turn signal switch. The Brake lights are wired through the turn signal switch, if the 3rd brake light works, the brake switch is OK. I don't think it has anything to do with the anti theft system (at this time)

is trailer lite fixture grounded good try and wiggle fixture when u hit signal. next try wiggle pig tail on trailer , still no signal. it must be wire from truck, trace back to connection and check all splices. to see if signal light works on trailer unhook pigtail and get a battery charger or another battery, connect a jumper from positive side to signal spot on trailer hook up. hook up ground as well see if light works if not its in the truck for sure.

Does the turn signals or hazards work in the rear?? Yes... it may be the brake switch or the turn signal switch (power goes from battery, to the brake switch then to the turn signal switch, then to the lights. No? .. again.. possibly turn signal switch or the wiring between cab and bed.

The only thing I can think of that would explain your problem is a faulty ignition switch.

My turn signals worked fine until last night when I ran my battery down and had to get a jump. I realized right away that my turn signals suddenly didn't work. My theory hasn't been tested, but I am going to unhook my battery cables and reconnect again to see if that does anything. If not, I'll check out the steering wheel and that big square thing by the fuses. Thank you for all the posts and I was so happy to find this web page!