Code P1605. I just bought this car from the auction and i took it to Autozone for diagnostics. Code 1605 was indicated. How do i repair this issue?

Kerry, you can't just disconnect the battery to fix things. Yes it clears the code from the computer memory, but can do damage.

You need an auto electrician with a pro grade scan took computer to read the Diagnostic Trouble Codes and the codes tell you the fix.

It is a known issue

https://www.google.com/search?q=2008+Toyota+Rav4++VSC%2C+and+Traction+Control+light+on

Diagnostic Trouble Code Chart - Toyota RAV4 Repair

https://www.toyotaguru.us > rav4-repair-2 > diagnostic-...
Jun 3, 2022 - Diagnostic Trouble Code Chart ; P0137. Oxygen Sensor Circuit Low Voltage (Bank 1 Sensor 2). - Open in HO2 sensor (sensor 2) circuit. - HO2 sensor ...


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P1605 is a manufacturer specific code that means different things depending on which manufacturer's products it is applied to.

LDV began life as a BMC vehicle that became Leyland-Daf and later after they went into receivership LDV emerged as a management buyout. Since that time LDV vehicles have been fitted with various engines and other equipment, I understand Peugeot has been a supplier to them but I have lost touch with them.

I suggest you ask an LDV dealer about the code or discover who supplied the management system and use that information to check their codes.

These codes are indicating a starting problem and rough idling. Code p1604 is a very vague code and diagnosing it without having a symptom is very complicated. And code p1605 is rough idling which means that the computer have noticed a rough idle situation usually this code is accompanied by other codes or if it's alone then I would suspect a fuel pressure issue. These two codes involve diagnosis and we'll need to dig into this problem deeper to find out what's causing them, Unless you are an experienced technician who need assistance then I will suggest that you take your vehicle to your local toyota dealership and they should be able to find the problem.

p1603 should help by reading this below
http://corolla-club.ru/doc1/c61151d7ba7b9bee3c247e42b685b253.html

OBD-II code P1603 indicates an issue with TCU communication.
There are communications that exist between the engine control module, or ECM, and the transaxle control module, or TCM. This communication is done through a control area network, or CAN. With the communication of the CAN, an independent pin and wiring is needed to receive a signal that includes sensor information from the ECM. The more information there is to communicate, the more wiring that is needed. When it comes to CAN communication, all of the information communicated is done alone control modules like the ECM and TCM using CAN lines. When there is a problem with these lines, the ECM will detect the problem and store a P1603 trouble code; the storing of the trouble code is what causes the SES or check engine light to illuminate on the dash.
Possible causes of trouble code P1603 include:

• Faulty transaxle control module (TCM)
• Faulty engine control module (ECM)
• Harness running from the TCM to the ECM has a short
• There is a poor electrical connection between the TCM and ECM

Diagnosing the exact cause of the problem should always begin with a visual inspection that could reveal bad wiring, loose connections, or damaged parts. From there, it is a matter of running down the list to determine what needs to be replaced. In general, a bad ECM will cause a loss of power, poor fuel economy, and stalling engine. While a bad TCM will have more prevalent transaxle issues like erratic shifting
P1605 and P1605
These codes are indicating a starting problem and rough idling. Code p1604 is a very vague code and diagnosing it without having a symptom is very complicated. And code p1605 is rough idling which means that the computer have noticed a rough idle situation usually this code is accompanied by other codes or if it's alone then I would suspect a fuel pressure issue. These two codes involve diagnosis and we'll need to dig into this problem deeper to find out what's causing them, Unless you are an experienced technician who need assistance then I will suggest that you take your vehicle to your local toyota dealership and they should be able to find the problem.
P1P

Hello Paige ! It sounds like you have a sick vehicle , lets see if I can help you fix it . Well the code you have has to do with lack of voltage to the ECM -engine control module.
P1633 - Keep Alive Power Voltage Too Low Indicates that the Keep Alive Power (KAPWR) circuit has experienced a power interrupt.

• Open KAPWR circuit
• Damaged PCM
• Intermittent KAPWR Circuit

2000 PCED On Board Diagnostics II SECTION 5: Pinpoint Tests Procedure revision date: 01/31/2001 QB: Diagnostic Trouble Code (DTC) P0603/P1605/P1633 > QB: Introduction QB1 CHECK BATTERY TERMINALS

Note: If KAPWR is interrupted to the PCM (that is, when a breakout box is installed or the battery is disconnected), DTC P0603/P1605 can be generated on the first power-up.

• Inspect the battery cables for loose connections, corrosion.

Are the battery terminal connections in good condition? Yes No KEY OFF. Battery terminals are OK. GO to QB2 . REPAIR battery terminals as necessary. QB2 INSPECT ENGINE COMPARTMENT FOR PROPER WIRE ROUTING

• Inspect Electronic Engine Control (EC) System wiring for proximity to ignition components or wires.

Is wiring too close to ignition components or wires? Yes No REROUTE as necessary. Engine compartment wire routing is OK. GO to QB3 . QB3 CHECK KEEP ALIVE POWER (KAPWR) TO PCM

Note: Refer to the PCM connector pin numbers in the beginning of this pinpoint test.

• Disconnect PCM.
• Measure voltage between KAPWR circuit at the PCM harness connector and ground.
• While observing digital multimeter, grasp the Electronic EC harness and wiggle, shake or bend a small section while working from the PCM to the dash panel.

Does the voltage reading indicate less than 10.5 volts? Yes No ISOLATE and REPAIR open circuit. No open in KAPWR harness circuit detected. GO to QB4 . QB4 CHECK FOR REPEAT OF DTC P0603/P1605/P1633

• Reconnect PCM.
• Start engine and allow it to reach operating temperature.
• Run Key On Engine Off Self-Test.
• Retrieve Continuous Memory DTCs.

Is DTC P0603, P1605 or P1633 present? Yes No REPLACE the PCM. REPAIR other DTCs as necessary. If none, testing is complete. You may want to take this to the repair shop , do you own a volt ohm meter ? Do you know how to use one ?

p 0031 is the heated oxygen sensor1 bank 1 replace itit is the one in the exhaust manifold before the cat converter
code p 0037 is the heated oxygen sensor in the other bank in the exhaust manifold before the cat converter code p 0418 refers to secondaryair injection(AIR) pump relay--circuit malfunction===replace the relay
code p 0102 refers to tye mas air flow (MAF) and the volume air flow(VAF) sensor ===causes --wiring short to ground---MAF/VAF sensors
code p 2188 refers to system too to rich at idle bank 1 by replacing the both heated oxygen sensores and cleaning /replacing the MAF/VAF sensors it should fix the problem

which engine option, we need that first. ?????????
2.4, 3.7L manual or automatic.???????????
1605, seems to be missing in my list. is this an autozoned, tool check? this code is bogus. typed wrong or not using a real scan tool that can read P1 Jeep FACTORY codes or correctly. (many cant)

the answer is in 2 places.
1: the FSM.
2: and training on how to fix cars. called diagnosis.

read here.
http://www.scantool.net/software/alldata-diy-1-month-subscription.html

some of the auto parts stores like autozone will check the code for you for free so you don't have to buy a scanner.

Just started this since your oil change? DIfferent viscosity? wrong filter?

it all depends on why the light came on.....could be as simple as running out of gas ...............lol. when the light comes on it is because the computer is recieving an error sygnal from any one of as much as hundreds of sensors. the only way to know is to read what the computer is indicating is out of it's parameters. there are error code readers, and autozone i believe will read the code for free. once the error code is detected you can take it from there as to how to proceed. non of the items you indicated in your question are serious or difficult to repair.