Secondary Air injection System Help P0418

I have been digging through this forum on this topic and haven't really been able to find another case with my specific case...

Here's the deal:

2013 TRD Sport DCLB ~80,000 miles

Trying to figure out a few things before I dump a bunch of money into replacing evrything

Throwing code P0418, truck runs as should, not in limp mode

The code came on randomly a few days ago, I had my mechanic read it and he reset it.

After code was reset (CEL an TRAC light not on) I could hear the system purge when I shut off truck. I drove around 25 miles or so with the code off, started and shut off truck a few times and always heard system purge on shutoff. I did not think to try and listen for it on startup and am not sure where I would hear it run. CEL and TRAC came back on and now I DO NOT hear the system purge on shutoff.

I tried swapping relays (fog lamps) but they still worked when I swapped (can anyone tell me exactly which relay is for this system? I tried 2 that I found through info on here)

Does this sound like the pump/valves may be failing or does this sound like it could be electrical or something?

Silly question, could a weak battery cause this? (I have not trouble with starting my truck but at my last oil changes they have showed that my battery is weak)

I appreciate any input and advice!

 

If the battery is known to be weak that would be a good starting point as a weak battery can cause strange gremlins.

From what I can tell P0418 has nothing to do with the valves or pipes, it has to do with the pump or pump circuit.
I can post the code chart for P0418 later but it doesn't appear to be terribly useful, basically it has you checking the pump and Air Injection Control Driver circuits and pump current.

 

Mechanical Codes

P1441 – Switching Valve No.2 Stuck Open Bank 1
P1442 – Switching Valve No.2 Stuck Close Bank 1
P1444 – Switching Valve No.2 Stuck Open Bank 2
P1445 – Switching Valve No.2 Stuck Close Bank 2
P2440 – Switching Valve Stuck Open Bank 1
P2441 – Switching Valve Stuck Closed Bank 1
P2442 – Switching Valve Stuck Open Bank 2
P2443 – Switching Valve Stuck Closed Bank 2
P2445 – Pump Stuck OFF Bank 1**
P2447 – Pump Stuck Off Bank 2

Electrical Codes

P0412 – SAIS Switching Valve ‘A’ Circuit Malfunction Bank 1
P0415 – SAIS Switching Valve ‘B’ Circuit Malfunction Bank 2
P0418 – SAIS Circuit/Relay ‘A’ Circuit Malfunction Bank 1
P0419 – SAIS Circuit/Relay ‘B’ Circuit Malfunction Bank 2

The following are Trouble codes NOTaddressed by the Gen 2 Bypass. These will require kit addon(s) in order to clear.

Pressure Sensor Codes

P2431 – Air Flow / Pressure Sensor Circuit Range / Performance Bank1
P2432 – Air Flow / Pressure Sensor Circuit Low Bank 1
P2433 – Air Flow / Pressure Sensor Circuit High Bank 1
P2436 – Air Flow / Pressure Sensor Circuit Range / Performance Bank 2
P2437 – Air Flow / Pressure Sensor Circuit Low Bank 2
P2438 – Air Flow / Pressure Sensor Circuit High Bank 2
P106B – Pressure Sensor Correlation / Evap. Pressure Sensor

 

The exact thing started happening with me, I’m at about 152,000km. Eventually you’re going to get P2441 and P2442 as well if you don’t fix it right away.

Don’t waste your time replacing it when an OEM (expensive) unit or an aftermarket unit. Just go with the Hewitt-Tech kit and forget about it forever!

https://hewitt-tech.com/product/sec...3-57/?sy=2013&sm=Toyota&smodel=Tacoma&se=4.0L

@hewitt-tech

 

Thank you for the info, I will definitely start by replacing the battery, with the code being under the "electrical" category maybe I'm just lucky enough that it's that....

 

This 100%

 

Thanks for reminding me about this. I'd read about the Hewitt solution previously & this post gave me impetus to go read thru the HS website & purchase a 4.0L 2nd gen bypass kit.

 

Well worth the money and free of headaches…literally plug and play unit!

 

@TegoTaco thanks for spreading the word!

@onemanmoshpit You are correct the P0418 points to the circuit in the Bank #1 Air Pump. Since it is located in the fender well it is not uncommon for it to take on water and short the circuit. That said, as you are experiencing it should only trip a check engine light and not put the vehicle into limp mode. I have include a few threads we have posted to give you some additional information about the failure prone SAIS. If you have any questions please do not hesitate to DM.

What Does the Secondary Air Injection System Do?
https://www.tacomaworld.com/threads/what-does-the-secondary-air-injection-system-do.780847/

What Do My Secondary Air Injection Error Codes Mean?
https://www.tacomaworld.com/threads/what-do-my-secondary-air-injection-error-codes-mean.780848/

How to Fix Secondary Air Injection System?
https://www.tacomaworld.com/threads/how-do-you-fix-the-secondary-air-injection-system.780849/

 

Kit arrived, very quick shipping, installed both the unit/wiring harness & the exhaust vent tube block-off plates on one of my off-road-only vehicles. Everything works as expected. No CELs, no codes, and it's nice not to hear the air pump running for half a minute at startup & then briefly at every shutdown. Easy to reverse should it be necessary or desirable.

Install took me about 2 hours, but that's because I was doing it first-time and working carefully. Now that I know what I'm doing I think I could install or remove same in about 30 mins or less.

Hardest part was getting at the 2 bolts on the #2 (towards front bumper) SAIS air valve exhaust tube flange. In my case I found it necessary to remove the air intake from the fender to the air filter. To get at one of the 2 air intake mounting bracket bolts I also removed the SAIS pump temporarily. Also temporarily moved the wiring harness bracket bolted just above the SAIS valves, and one of the tubing connections from the SAIS pump to the valves.

 

@GilbertOz Your post is music to our ears. We have tried to engineer the HT Bypass Kit to be as DIY friendly as possible. That said, some of those flanges to install the Block off Plates can take a little longer to access. If there is anything else we can assist with please do not hesitate to contact us.