'06 Secondary Air Injection Pump Relay A

I got a CEL with a code P0418. When I took the air pump apart, the motor was dead, so I replaced the pump. The motor in the new pump worked fine. The CEL cleared out for a brief time when I disconnected the battery for several minutes. However, the CEL has come back on. I'm wondering if the relay is bad, but I don't know where it is physically located. I found the 50 amp fuse and it is good. Can someone please tell me where the relay is located and, if it is in a location with other relays, how to identify it. Thank you.

 

There is no relay for the secondary air system, it is controlled by the Air Injection Driver Module located on the right fender near the firewall. Basically you need to check powers and grounds at the AID module, the wiring between the module and the secondary air pump, and the pump itself.

 

Dm93, thanks for the info. I will check things out as you suggest.

 

I have done a continuity check on the two wires that go from the Air Injection Control Driver to the Air Pump. The black wire shows continuity, but the white wire shows to be open when measuring at the female terminals in the plugs at each end of the wire. I'm reluctant to cut the open wire at the plugs to replace it without making sure where the open is. Any suggestions?

 

The White/Black wire from the pump goes direct to ground, the White wire at the AID module is power in from the 50A A/PMP fuse.

 

@jerlin This is an electrical Secondary Air Injection error code. Below I have included a link to a recent thread that provides some additional details. If you have any questions do not hesitate to reach out, DM or give us a call.

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

 

Wanted to post this since the threads really helped me troubleshoot this but there doesn't seem to be a post that matches what I've experienced. 2009 2.4l (2nd gen) 4x4 pushing 250,000 with five speed manual.

Had a bit of a rough idle during a cold start in mid January. Shortly afterwards, engine would noticeably shake during a cold start. When checking things out, noticed coolant was low - took about 1/2 a gallon. Soon the CEL would indicate a misfire on cylinder 3. Looking here, I thought it was the dreaded head gasket leak. Made an appointment with mechanic and started looking at what was out there on the used car market. Was still able to drive it since it ran great after warm up - just cleared the code so it wouldn't go into limp mode.

Mechanic pulled the plug and it wasn't burning coolant. Turned out it was just a leak. Of course the rough idle issue on cold start didn't happen until the third day at the shop. They said they cleaned up the fuel injector, fixed the coolant leak, and sent me on my way. Two weeks later, same rough idle and misfire code started showing up.

Instead of taking it back to the shop, I fired the parts cannon at it figuring why not - it is old enough to get new parts. Over the course of a few weeks, I cleaned the air filter (have cold air intake) and throttle body (didn't remove it, just wiped around the butterfly valve with throttle body cleaner) then replaced the MAF sensor, MAP sensor, and PCV valve. I poured a crap ton of fuel injector cleaner in the tank too just for some good measure. Somewhere around then, my battery light went on so replaced the alternator. What was weird was each time I cleared the code/disconnected the battery, it would run fine for a few days like the computer was having an issue figuring out the air/fuel mixture at idle. One or a combination of those things must have worked because the rough idle and misfire code went away and then popped up the secondary air injection codes! This time I couldn't clear the code but I was fortunate that it didn't go into limp mode at all.

Fire number 2 of the parts cannon! Replaced the air switching valve, air pump, and air injection control. There were a couple of codes that kept popping up but the one that stuck was P0148. Here's where I could have saved a bunch of time and money: get a good multimeter to do some basic diagnostics (the free one at harbor freight is NOT accurate enough and you can get a decent one for <$50), create an account here to download the guides, and BUY OEM PARTS for the secondary air stuff! I originally bought the switching valve and air pump on Amazon not heeding the posts here. When the code didn't clear with those replaced, I found a good deal on an OEM air injection control module on ebay. When the code still wouldn't clear, I decided I'd try another air injection control valve since I thought it might be bad wiring in the cheap one I bought; again, ebay had a good deal on an OEM one but it was a bit different; had to buy longer bolts to get it to mount to the engine. When the new control valve didn't clear the code, I finally created an account here to download the diagnostics page and thought I had a bad ground using the harbor freight meter. Double checking it with a better one, discovered the ground was good but the resistance on the pump motor pins was way too high; the new motor was shot! Tested the old one and it was still good - go figure - just replaced the filter since the original foam one wasn't there. **knock on wood** no more codes!

So I still may have saved a bit of money from taking it to the mechanic, the parts were about the same price as the lock out kit (and it is still street legal), but man it was a long few of months. Hope this helps someone with similar issues and thanks for all those who posted on this thread and the others.

**Update** It's been a few months and I noticed truck was getting slower to start; no surprise since the battery is about six years old. Go to start it one cold morning, it barely cranks, and lo' and behold the CEL comes on with a secondary air injection code after it starts up! I clear it, install a new battery that afternoon, and no troubles ever since **knock on wood**. I have a feeling that part of the gremlin I was hunting down all that time was the battery just conking out from when it was colder or sitting for awhile. So if you're running into those trouble codes, try checking your battery as well.