Your CAC Card Costs $128 to Replace—Take Care of It

That piece of plastic in your wallet represents significant government resources: the card itself, encoding, issuance, and the time you’ll spend at the ID card office when it fails. Physical damage is the leading cause of premature CAC failure, and most of it is preventable with basic care.

This guide covers practical CAC maintenance that keeps your card working until its natural expiration date—no trips to DEERS required.

Understanding Why CACs Fail

Your CAC uses contact-based chip technology. Those eight gold contact points on the chip surface must make clean electrical connections with the reader’s contact pins. Any contamination, oxidation, or physical damage interferes with this connection.

The chip itself is remarkably durable—the contacts are the weak point. Unlike the magnetic stripe on a credit card, CAC contacts carry bidirectional data and power. A barely-visible layer of oxidation that wouldn’t affect a credit card can cause intermittent CAC failures.

Bent Reader Pins: The Most Common Problem

CAC readers have spring-loaded contact pins that press against your card’s chip surface. These pins bend easily, especially when cards are inserted at angles or forced into readers that already contain debris.

Signs of bent reader pins:

• Card works in some readers but not others
• Intermittent “card not recognized” errors
• Reader makes inconsistent contact (wiggling the card helps)
• Works when inserted “just right” but fails otherwise

Inspect your reader by looking directly into the card slot. The contact pins should all be at the same height and properly aligned. If any pins appear bent or misaligned, the reader needs replacement—don’t try to bend pins back into position.

Cleaning Your CAC Contacts

Clean contacts monthly, or immediately if you notice reliability issues. Use a soft, lint-free cloth—microfiber works well. Never use abrasive materials or metal tools on the chip surface.

For light cleaning, a dry microfiber cloth removes fingerprints and light oxidation. Wipe in one direction across the contacts rather than circular motions that could spread contamination.

For stubborn oxidation, slightly dampen the cloth with 91%+ isopropyl alcohol. The high-concentration alcohol evaporates quickly without leaving residue. Avoid rubbing alcohol formulations with added moisturizers—they leave film on the contacts.

After cleaning, allow the card to dry completely before insertion. Inserting a damp card can cause reader damage or electrical faults.

Preventing Physical Damage

Use a protective sleeve: Your CAC came in a plastic sleeve—use it. Contact with keys, coins, and other cards causes scratches and accelerates oxidation.

Don’t carry it in back pockets: Sitting on your CAC flexes the card body, which can crack the embedded chip. Front pocket or badge holder only.

Avoid extreme temperatures: Cars in summer can exceed 150°F internally. Chips are rated to survive this, but repeated thermal cycling weakens internal connections. Don’t leave your CAC on the dashboard.

Remove before going through X-ray: Security X-rays won’t damage the chip, but the physical handling often does. Cards get bent, scratched, and contaminated in security bins.

Reader Maintenance

Your CAC reader needs occasional cleaning too. Debris accumulates in the card slot over time, transferring to your CAC’s contacts.

Compressed air removes loose particles from the card slot. Use short bursts rather than continuous spray, and hold the can upright to avoid propellant residue.

For internal contact cleaning, specialized smart card reader cleaning cards are available. These cards have a mildly abrasive surface that cleans reader contacts during insertion. Use sparingly—once every few months is sufficient.

Environmental Considerations

Humidity accelerates oxidation on gold contacts. If you work in high-humidity environments (outdoor, maritime, or tropical climates), check your CAC contacts weekly for green or white oxidation buildup.

Static electricity can damage chip electronics in extreme cases. In low-humidity winter conditions, touch a grounded metal object before handling your CAC to discharge static.

When Cleaning Doesn’t Help

If you’ve cleaned both the CAC and reader but still experience issues, the problem may be internal chip damage rather than contact contamination. Signs of chip failure include:

• Card fails consistently across multiple known-good readers
• PIN validation fails even with correct PIN
• Certificate errors that persist after reinstalling DoD roots
• Visible chip cracking or delamination

Internal chip damage requires card replacement. Visit your nearest ID card office with two forms of ID. While inconvenient, addressing a failing card proactively beats being locked out of systems at a critical moment.

Proper CAC care takes minimal effort but prevents significant frustration. A few minutes of monthly maintenance keeps your credential working reliably for its full three-year validity period.