B1601 on Lexus
PATS Received Incorrect Key-Code From Transponder
B1601 on Lexus vehicles indicates pats received incorrect key-code from transponder. Au7o has documented this code across 1 Lexus model — most commonly on LS. B1601 is a Ford/Lincoln/Mazda body code indicating the Passive Anti-Theft System (PATS) received an incorrect or unrecognized key-code from the ignition key transponder. The anti-theft module could not validate the key, so it may prevent the engine from starting (no-start) and the theft/security light typically flashes. It is not a mechanical engine fault but a security/authentication issue between the key and the immobilizer. Resolving it usually involves key relearning or addressing transponder/wiring faults. Typical repair costs on Lexus range from $400 to $1,500, depending on the specific model and root cause.
Common Causes of B1601
- •Unprogrammed, damaged, or wrong transponder key
- •Key not properly learned to the vehicle
- •Faulty or weak transponder/key chip
- •Faulty PATS transceiver ring at the ignition
- •Damaged wiring/connector between transceiver and module
- •Faulty PATS/anti-theft control module
B1601 on Lexus by Model
Lexus LS(1 issue)
- Self-Leveling Headlight System Failure2007-2017
The adaptive self-leveling HID headlight system fails due to deterioration of the headlight level sensors mounted at the front and rear suspension. The sensors develop internal failures from exposure to road debris and moisture, causing the headlights to aim incorrectly or trigger warning lights. Replacement sensors are expensive OEM-only parts.
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View B1601 across all makes →Frequently Asked Questions
What does B1601 mean on Lexus?▼
B1601 stands for "PATS Received Incorrect Key-Code From Transponder." B1601 is a Ford/Lincoln/Mazda body code indicating the Passive Anti-Theft System (PATS) received an incorrect or unrecognized key-code from the ignition key transponder. The anti-theft module could not validate the key, so it may prevent the engine from starting (no-start) and the theft/security light typically flashes. It is not a mechanical engine fault but a security/authentication issue between the key and the immobilizer. Resolving it usually involves key relearning or addressing transponder/wiring faults. On Lexus specifically, this code is documented across 1 model.
What causes B1601 on Lexus vehicles?▼
Common causes on Lexus: Unprogrammed, damaged, or wrong transponder key, Key not properly learned to the vehicle, Faulty or weak transponder/key chip, Faulty PATS transceiver ring at the ignition, Damaged wiring/connector between transceiver and module. Specific causes vary by model and year — see the per-model sections below.
How much does it cost to fix B1601 on a Lexus?▼
Repair costs on Lexus range from $400 to $1,500, depending on the specific model and root cause.
Which Lexus models have B1601 documented?▼
Au7o has documented B1601 on 1 Lexus model: LS.