How do i determine of my 2008 hyundai elantra is negative grounded or positive grounded?

Fuse or relay bad

Removal & Installation

Specific to:
Hyundai Entourage 2007-2008

1. Before servicing the vehicle, refer to the Precautions Section.
2. Disconnect the negative (-) battery terminal.
3. Remove the crash pad lower panel (A).
   
   
   
   Fig. Remove the crash pad lower panel (A)
4. Remove the 2 screws (A) and the trip switch connector.
5. Remove the crash fascia panel (B).
   
   
   
   Fig. Remove the crash fascia panel (B)
6. Remove the screw with the ignition in the ON position (IG ON) and disconnect the 6P connector.
7. Remove the ignition switch (A).
8. Installation is the reverse of removal procedure.
   
   
   
   Fig. Remove the ignition switch (A)

Specific to:
Hyundai Accent 2006-2008
Hyundai Azera 2006-2008
Hyundai Elantra 2006-2008
Hyundai Sonata 2006-2008
Hyundai Tiburon 2006-2008

1. Before servicing the vehicle, refer to the Precautions Section.
2. Remove or disconnect the following:
   
   The negative battery terminalThe crash pad lower panelThe ignition switch after loosening the screw with IG ON and disconnecting the 6P connector
3. Installation is the reverse of the removal procedure.hope this helps it is off autozone website

On this website you find fuse box description for Hyundai Elantra (2008 - 2009)

http://www.autogenius.info/hyundai-elantra-2008-2009-fuse-box-diagram

the positive lead has the larger terminal on it as the battery posts are different sizes. the small terminal goes on the small post and the wire runs to the engine or body as the earth .. Positive leads are coloured red while negative leads are black.

Car Radio Constant 12v+ Wire: Red
Car Radio Switched 12v+ Wire: Green/Black
Car Radio Ground Wire: Black
Car Radio Illumination Wire: Yellow
Car Stereo Dimmer Wire: Black/Orange
Car Stereo Antenna Trigger: Green
Left Front Speaker Positive Wire (+): Black
Left Front Speaker Negative Wire (-): White
Right Front Speaker Positive Wire (+): Blue
Right Front Speaker Negative Wire (-): Red
Left Rear Speaker Positive Wire (+): Black
Left Rear Speaker Negative Wire (-): Yellow
Right Rear Speaker Positive Wire (+): Green
Right Rear Speaker Negative Wire (-): Orange

On this website you find fuse box description for Hyundai Elantra (2008)

http://www.autogenius.info/hyundai-elantra-2008-2009-fuse-box-diagram

Check to see if any of the wires have a single wire running off of it to the body somewhere, or attached to a bolt on the intake somewhere. This will indicate that it's a grounded wire, which means the battery wire attached to it will be your negative wire.

Your positive will run to a bunch of other wires, and into modules and starter and alternator and other electrical products.

I hope this helps, post back if still unclear!

make sure your radio and ignition switch is off.first you disconnect negative cable first then the positive cable.then you replace new positive battery cable first then you hook the negative battery cable back up last.

1. Disconnect the negative (-) battery terminal. 2. Remove the front side cover screw. 3. Remove the front fog lamp assembly connector (A).

4. Remove the front fog lamp bulb (A).

Verify (test) the battery is good/charged. Verify good, clean cable connections (positive & negative, correct polarity). Inspect positive and negative cables for loosness (positive cable condition to starter connection - clean/tight) negative cable condition to ground connection clean/tight). Replace/repair/clean/tighten cable(s) as needed. Did you remove/disconnect any components from the engine when you replaced the battery? If so, did you remember to put/reconnect them back?