Battery Terminal

This procedure covers the removal, cleaning, or replacement of battery terminals on a 2007 Ram 3500 with the 5.9L Cummins diesel engine.

Warnings

Tools required

Parts

• Battery terminals (if replacing) × 2 — Use OEM specification or quality aftermarket
• Battery terminal anti-corrosion washers × 2 — Felt washers (optional)

Preparation

1. Ensure the engine is off and the key is removed from the ignition
2. Open the hood and locate both batteries on the driver's side of the engine compartment
3. Identify which battery or terminals need service (front battery connects to vehicle systems, rear battery provides starting power)
4. Ensure adequate ventilation in the work area

Procedure

1. 1

   Disconnect negative terminal from front battery
   Using a 13mm wrench or battery terminal wrench (verify size, some clamps use 8mm or 10mm), loosen the nut on the negative (black or marked with minus sign) cable terminal on the driver's side battery. Remove the cable from the battery post and position it away from the battery to prevent accidental contact.
2. 2

   Disconnect positive terminal from front battery
   Loosen the nut on the positive (red or marked with plus sign) cable terminal on the front battery. Carefully remove the cable from the battery post. Be careful not to let the terminal contact any metal surfaces.
3. 3

   Disconnect negative terminal from rear battery
   Locate the negative terminal on the rear battery. Loosen and remove the negative cable terminal, positioning it away from the battery post.
4. 4

   Disconnect positive terminal from rear battery
   Loosen and remove the positive cable terminal from the rear battery. Note the interconnect cable between the two batteries if present.
5. 5

   Inspect terminals and cables
   Examine all terminals and cable ends for corrosion, cracks, or damage. Check cable insulation for wear or damage. If terminals are severely corroded or damaged, they should be replaced rather than cleaned.
6. 6

   Clean battery posts and terminals
   Using a battery terminal cleaning brush, clean the inside of each cable terminal and the outside of each battery post. For heavy corrosion, apply baking soda and water solution to neutralize acid, scrub with wire brush, then rinse with clean water and dry thoroughly. Clean both batteries.
7. 7

   Install terminals on rear battery
   If installing new terminals, attach them to the cables first according to manufacturer instructions. Place the positive terminal on the positive post of the rear battery first, ensuring it sits flush on the post. Hand-tighten the terminal nut, then snug with wrench (do not overtighten). Repeat for negative terminal.
8. 8

   Install terminals on front battery
   Install the positive terminal on the front battery positive post, ensuring proper seating and connection. Tighten securely. Then install the negative terminal on the negative post and tighten.
9. 9

   Apply terminal protector
   Apply battery terminal protector spray or anti-corrosion grease to all terminals and exposed battery posts to prevent future corrosion. Alternatively, install felt anti-corrosion washers if not already present.

Reassembly

1. Ensure all terminal connections are tight but not over-tightened, which can damage the battery posts
2. Verify that positive and negative terminals are correctly positioned and not touching any metal surfaces
3. Check that interconnect cables between the dual batteries are properly secured

Verification

• Turn the ignition to the ON position (do not start) and verify dash lights illuminate normally
• Start the engine to confirm proper electrical connection and starting function
• Check that all electrical accessories function properly (lights, radio, windows, etc.)
• Inspect terminals for any signs of sparking or loose connections
• Reset clock and radio presets as needed

Related trouble codes on this vehicle

Codes that commonly send this job to the bay — tap one for symptoms, causes, and diagnostic steps.

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