How to fix Toyota P1605 fault code?

[StNorah]

Toyota P1605 fault code means: Knock Control - Malfunction. The Powertrain Control Module (PCM) uses knock sensors to detect vibrations when engine speed changes. The knock sensor then expresses this vibration in the form of voltage. When necessary, the Engine Control Unit (ECU) will prevent knocking by delaying ignition, etc. It is recommended to clear the fault code. If the same fault code appears, the Engine Control Module may need to be replaced. More details are as follows: 1. Toyota Motor Corporation, abbreviated as TOYOTA, is a Japanese automobile manufacturer headquartered in Toyota City, Aichi Prefecture, and Bunkyo, Tokyo, Japan. It belongs to the Mitsui financial group. 2. The meaning of the TOYOTA logo (established in October 1989): This logo was released in October 1989, on the 50th anniversary of TOYOTA's founding. The design focuses on an elliptical left-right symmetrical composition. The ellipse is a curve with two centers, representing the heart-to-heart connection between car manufacturers and customers.

[Drew]

Encountering the P1605 trouble code on your Toyota can be quite frustrating. I had a similar issue with my old Camry before—it mainly indicates a problem with the starter system. Don’t panic yet; first, check if the car can start normally. If it fails to start, the battery might be dying, or the starter motor could be worn out—this part tends to wear over time with prolonged use. Other possible causes include loose wiring connections, blown fuses, or even a faulty engine control unit (ECU). I recommend checking the battery yourself first. Use a voltmeter to test it; if it reads below 12V, it’s time for a replacement. Also, inspect the relevant fuses in the fuse box, which is usually located under the steering wheel in Toyota models. If you can’t resolve it, take the car to a professional repair shop—they have diagnostic tools to pinpoint the issue accurately. Avoid forcing a start, as it could damage more components and cost you more in repairs. Remember, regular maintenance of the starter system can help prevent such hassles in the future.

[GriffinAnn]

When I was driving my Toyota and encountered the P1605 error, my first thought was that the car wouldn't start. This trouble code usually indicates an issue with the starter or related circuits. You can perform some simple checks yourself: confirm whether the battery is dead by testing if the lights or radio work; then check for loose or corroded wiring connectors in the engine compartment. If these seem fine, the problem might be a faulty starter or ECU control failure. When I dealt with it, I drove straight to the 4S shop—they can diagnose it faster and more accurately with a computer. Sometimes, replacing it with a used starter solves the issue for just a few hundred bucks. To prevent this, avoid frequent starts to reduce system strain. For safety, if the car doesn't start, don't force it—call a towing service instead.

[Harold]

When a Toyota displays the P1605 fault code, it indicates an issue with the starting system. Simply put, the starter motor may not be responding to commands. There are several possible causes: first, insufficient battery power, leading to weak starter performance; second, poor contact within the starter's internal relay; third, a short circuit or open circuit in the wiring; fourth, an ECU signal error. What interests me is using an OBD scan tool to read detailed error codes, which can accurately pinpoint which component has failed. If it's the battery or a fuse, replacing them yourself is straightforward; but if the starter motor or ECU is faulty, it's advisable to seek professional mechanic assistance. Don't underestimate this problem—delaying repairs could potentially damage the engine. Regularly listen to the starting sound during vehicle use to detect any unusual noises early and prevent issues.