Replaced Injection System fuse (p0418)then engine light came back on/why?

Question

Was given codes p0418 and p1604 at O'Reilly, no start up issues with truck. Discovered #15 fuse was missing completely, therefore replaced it. After driving it over 100+miles the check engine light has reappeared. There were very noticeable changes after inserting the fuse with the ac and throttle. We are at a loss, we popped the cover to check and the fuse is still in place and just fine. Never really addressed the p1604 code, however I correlated that with issues I've read people having with their engine starting when experiencing issues with the injection system fuse.

Answer 1

P0418 Secondary air injection system

The air injection fuse is a 50 amp fuse. P1604 is startability malfunction. this can range from the anti theft to to low battery or anything that would create a hard to start situation. If the air injection fuse went open for bank 1 you would also set a EGR code. unfortunately Toyota does not list what a fuse 15 is it list only by names such as EFI or A/F.

Comments

I greatly appreciate you taking a moment to assist me in resolving this issue. My owner's manual reads as follows on pg 577: #15 fuse (AI PMP HTR)-10 A-Air Injection System. This is where I got the idea that a 10 amp belongs in that slot, plus my husband has an identical truck with the exception his is a 5.7 liter. His fuse box contains a 10amp in the #15 slot, whereas mine had no amp what so ever. Not quite sure how that was possible unless it wasn't installed to begin with (which makes no since, I've had my truck for 4 years, no issues until now)... I am going to head back down to O'Reilly in a sec to get them to run the codes again and check my battery (which is only 1 month old)...so we shall see. Fun times...

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I have a Toyota park here, I went thru the owner manual and check the fuse box , there is a fuse 15 slot and it listed as air injection Bank 2 and fuse 16 has a list as air injection Bank 1  .  The code P0418 is for Bank 1 so there should be a fuse for slot 16. P0418 . In a lot of case when dealing with P0418 what happens is the air injection pump is on just during a cold start for at least 30 seconds. , and the fix is simple we traced the problem to the relay for the air injection pump, hopefully that would be it, and if it was it set a P0419 with it. but this is worth checking into. Then again P0418 is so popular that the majority of the fixes was because water went into the air injection pump inlet side that rendered the air pump useless, and if that the case the air pump is replaced, As for the P1604 this just means there is a hard time just to start the engine. which is not even related to P0418. The dealer had a extended warranty for the air injection pump due to water entering the inlet side. it may be covered.

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Oh wow.. ok..Thank you for placing my mind at ease.. I had read people having a direct issue with their secondary air injection pump, giving them a p2... number. We have had a lot of strange various issues between 2 Toyota dealerships regarding bad services experiences during simple oil changes and inspections. Therefore we don't trust any of them anymore. We took the truck down this morning and thankfully only have the P0418 code still coming up. Like you, after reading and reading alllllll the info I could find... I'm thinking and praying its a relay issue... I called the corporate office of Toyota afterwards. The lady wants me to take it to a Toyota Dealership for them to verify the code is correct. To my prior understanding that is a 125.00 charge that I am just not willing to dish out to any of those people. She did tell me the 2012 models are not covered under that extended warranty.... and it completely baffles me that they would place this pump in such a difficult place knowing they had such issues with the previous models. You are awesome! Thank you... I read the #16 slot is the charging system... didn't think twice about it... so will go check the fuse right now!!! Thank you thank you thank you... you are awesome!!!

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The reason I bring up the warranty issue , is that P0418 and P0419 was caused by water intrusion on the inlet of the air injection pump , It was in Canada that Toyota was forced to Recall the air injection pump and upgrade the inlet section of the air injection pump.

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I read where only certain models fall under that extension (2007 to 2010).... Oddly enough I can't find anything regarding issues specific to the 2012 anywhere. All other models are built differently. Was attempting to simply figure out what it looks like or where to locate the relay... no luck via the web or owner's manual. I just ordered a repair manual on amazon hoping this should help.