B1602Anti-Theft

Invalid / Missing PATS Key Code

B1602 indicates the passive anti-theft system (PATS) received an invalid or missing key code. The transponder was not read correctly, so starting may be blocked.

🚗 Often not, since the anti-theft system may prevent starting with an invalid key.
MEDIUM
severity
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🎯 Top Causes, Ranked by Likelihood

#1Unprogrammed or damaged key$50-$300
40%
A key that is not programmed or has a bad transponder is rejected.
#2Faulty transceiver/antenna ring$100-$350
30%
The ignition antenna fails to read the key chip.
#3Wiring or module fault$100-$400
20%
A wiring or PATS module fault disrupts key reading.

🩺 Common Symptoms

💰 Repair Cost: DIY vs Shop

DIY Cost
$50-$300
Shop Cost
$150-$500

📋 Free OBD2 Code Cheat Sheet

The 50 most common codes with likely cause and DIY fix cost. Sent once, no spam.

🔧 How to Diagnose B1602

1Try a known-good programmed key
2Inspect the ignition antenna ring and connector
3Scan for PATS-related codes
4Reprogram keys or repair the antenna as needed

❓ Frequently Asked Questions

What does B1602 mean?
The anti-theft system did not get a valid key code, so it may block starting.
Will a spare key fix B1602?
Sometimes, if the original key is unprogrammed or damaged.
What causes B1602?
A bad or unprogrammed key, or a failed antenna ring at the ignition.

🔗 Related Codes

B2799B2960B1600U0155
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