P0418 and P2438 DTC codes

Last month, I purchased a 4.0L 6-cylinder 2014 Toyota Tacoma Limited TRD Sport Extended Cab Pickup 4-door. It came with 120k miles and was previously vandalized according to the private seller (He owns a mechanic shop and fixes up 1st gen Tacomas). He gave me a list of the problems to fix. There weren't any serious problems to fix; just an AC vacuum and recharge, brakes were soft, new secondary air pump, and passenger door window won’t roll down. He had also told me that there was a check engine light. I have fixed most of these problems except for the check engine light and secondary air pump. To add on, it is currently under Limp Mode.



I scanned with my OBDII and it displayed permanent DTC codes: p0418 and p2438. For P0418, I have checked the secondary air pump that came with the Tacoma, and it worked as it should whenever I connected it with a 12V battery. However, when I would cold-start the Tacoma, it does not turn on. I’ve used a multimeter to measure resistance and continuity in the harnesses; everything was fine between the air injection control driver and the secondary air pump. Relays were good. Switched Air Pump HTR relay with the Seat HTR and still displays the code. I bought an $20 AllDataDIY subscription, and it has led me to the conclusion of the air injection control driver being at fault. When I checked the air injection control driver, it displayed part number: 89580-35020. (Which is meant for 3rd gen Tacoma I believe, but it should be 89581-60010. Correct me if I am wrong.)


For P2438, I am still working on it, and will be using AllDataDIY to diagnose the problem. My suspicion is probably the Secondary Air injection Pump Check Valve.


I do not plan on buying a bypass kit as I still need to transfer the title ownership. Texas does not allow bypass kits when performing a visual inspection of the vehicle.



Before buying a 2nd gen air injection control driver, the question I have is that will the 3rd gen air injection control driver on a 2nd gen Tacoma cause the P0418 code? Or could the p2438 code affect the secondary air injection pump into not operating when starting up?

 

First off if you have a 2014 with a V6 it's a 4.0L not a 3.5L.

Note very common for the AICD to fail, the air pumps and valves are relatively common though.
Do you have a scan tool that can view SAIS data and also bi-directionally control the SAIS?

Have you used a test light to check powers and grounds at the Air Injection Control Driver?

Pin 1 (White) of the 2 pin connector should have Power at all times.

Pin 1 (White/Black) of the 6 pin connector should have Ground at all times.

Pin 5 (Blue/White) of the 6 pin connector should have Power with the key on.


At the Air Pump

Pin 2 (Black) should have Power when the Air Pump is commanded on.

Pins 3 & 4 (White/Black) should have constant Ground.

 

Thank you for your response. I apologize for the confusion, and have corrected it. First time owning a Tacoma.

Unfortunately, I do not have scan tool that can view SAIS data and bi-directionally control the SAIS.

However, I was able to do most of the instructed tests you've mentioned.

The powers and grounds at the Air Injection Control Driver were all good.

At the Air pump, Pin 3 & 4 did not show light when checking Ground.

 

Just to be clear: test light from battery Positive to Pin 3 or 4 you got no light?

 

Thank you for the clarification.

I was able to get light from battery positive to Pin 3 or 4.

 

Have you applied power to Pin 2 and ground to pin 4 of the air pump to see if it will run?

 

Yes, I have done what you've mentioned and it runs.

 

Well if the wiring checks out between the AICD and the PCM that's about all the checks you can do without a bi-directional scanner and oscilloscope.

Being it's not a common to fail part I think I'd try to find a used one.

 

Hey @Dm93, I appreciated your help with the P0418 code last time. However, I had to hold off on fixing that code until an auto electrician checks it out; Purchasing an used OEM Air Injection Control Drivers can be costly and be a gamble, especially if it didn't fix the code.

Moving on to the next code , P2438, I was wondering if there was a way to test if secondary air injection valves are any good. Or is there anything else that can be affecting this code? Thank you.

 

Well I mean a used one can be had as low as $40 and a new one looks to be over $300 so...

The sensor is integral to the valve, Pin 2 (Blue/Yellow) is the 5v Ref, Pin 3 (Black) is the Air Pressure Signal, and Pin 4 (Brown) is Sensor Ground. Should be pretty easy to check circuit integrity, would be really easy if you could read the air pressure with your scanner.