Readiness is tricky. Unless you are up against a time clock I'd just drive the truck as normal until it goes ready. Took mine like 2 days.
EGR Readiness Achieved with EGR Removed! (2 Viewers)
- Thread starter SuperHatch
- Start date
This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.
I'm up against a deadline. Of course the problem popped up two weeks before that deadline....
Be patient when following the drive cycle. It doesn't always work the first couple times.
So I had something weird happen today during my commute. So like i previously mentioned I put the relay in last night for my drive today around 70 miles. All day everything's going great I can hear the relay clicking at cruising speeds and no CEL. I'm thinking to myself "alright you got it figured out" until BOOM! Freakin CEL. So I finish my daily driving and try not to let it get to me as you had previously mentioned it takes a few cycles. Well when I got home I plugged the reader up and am now getting a P0141 code dealing with my o2 sensors. Is there something I did wrong hooking my relay up? or is my luck really just this bad?
Make sure you check your wiring diagram for your specific year. There were some changes on those terminals throughout production from year to year. When I originally did it I was going off someone else's diagram and it was the wrong item. The relay should really only be clicking with throttle inputs, normally from 0+ or returning back to 0. Doesn't normally click on and off while under load, at least in my experience.
Yea it definitely responds with the throttle. What year was the diagram you posted for?
1996
I'm leaning towards it being a new unrelated issue. Especially since I did the relay and never got a 401 code. Where prior to the relay I was getting a set code at 30-40 miles.
Just wanted to update the forum on my situation. Good news is I passed emissions test, the bad news is that i have terrible luck. It was purely coincidence that my O2 sensor decided to go bad after putting the relay on the computer. So after putting in a new O2 sensor in, 100 miles latter boom rediness and passed emissions.
Wired up @AppleTech's relay yesterday (Huge thanks for the research and idea!!!), so fingers crossed
. Wires on my '97 were the same. Assuming it works for me too, I'll remove it and give it to anyone that needs it for the cost of shipping. Edit: relay has been donated. Here a few pics of the taps I made with T-Taps under the glovebox if it helps anyone:
. Wires on my '97 were the same. Assuming it works for me too, I'll remove it and give it to anyone that needs it for the cost of shipping. Edit: relay has been donated. Here a few pics of the taps I made with T-Taps under the glovebox if it helps anyone:
Last edited:
Update: Installed the relay and went for a drive. One thing to note is that I used an 80KΩ resistor for the "cold" side since the FSM calls for values between ≈65KΩ and ≈95KΩ. So with a freshly cleared ECM, I took off. A scangauge doesn't update readiness real time, but after about 10-15 minutes I scanned it and it was already "Ready". Woo Hoo. I left the relay socket in the rig and jumpered the ground to the high temp side resistor just in case I ever need to re-live this process...
Outsane
Supporting Vendor
I would like to borrow the set up, are you in San Diego? 619 area code
Sorry to bring an old thread up here but thought it was worth a little follow up on what I experienced and to also throw out a thanks for all those that contributed to this thread and the one in post #2. This whole thing certainly was not easy to follow as a whole but guessing a good write up wouldn't go well here considering what your doing by cheating the system. I'm my case the P0401 code is very intermittent and ALWAYS seems to come up when I need to get emissions passed while seemingly rarely on otherwise.
My situation:
- 97 Land Cruiser. Same pinout as shown in post #40 and a 1996. Also NOT the same as the original post.
- I simply skipped all the bebe's in the TB hoses and since 2 hoses are between the TB and ECR valve I looped each back on itself and hooked on the factory mounts near the throttle linkage between each to look factory.
- I also used the same wiring harness posted in #45 which worked out great. The one issue I personally hit a wall on is I first added the 80 ohm resister that 619toy listed above but the only on I could find was a 25W monster that looked nothing like the others. I couldn't get the trigger to work so had to order a 100 ohm which I ended up still having an issue with due to my soldering skills so bypassed this and it worked perfect. The readiness came extremely quickly so I have no worries about the fluttering of the relay trigger. Especially due to the fact the relay is pulled when readiness is achieved. I'm not an electrical engineer and was showing voltage on both sides of the trigger so guessed the issue was the VSV was not grounding when triggered and almost started digging into it.
- After all reset I did the 4.7K resister on the temp probe by simply cutting the wire on the probe side of the connector and adding the resistor leaving everything in place yet looping the computer side and pushing into the factory heatshrink to get out of site.
- Last Item is I achieved readiness before clearing the last code with the check engine light on for some silly reason but after getting system readiness and the engine light cleared on its own I was still showing the P0401 code with readiness and no check engine light. I thought it was possibly my terrible scan tool I was using. I ended up going to get emissions rather than trying to go thru the whole process again. Even though showing this code they passed the emissions because the check engine light was functional and all systems were showing ready. Not sure if this is normal or the girl there doing me a favor? Seemed kind of silly since this seems to be the whole reason behind mandatory emissions testing here.
Last item, anyone in North Colorado the Fort Collins station off I-25 can now test vehicles with large tires so you wouldn't have to go thru all this nonsense anymore. You can test your emissions on the AWD system with no need to dig into your OBDII system.
My situation:
- 97 Land Cruiser. Same pinout as shown in post #40 and a 1996. Also NOT the same as the original post.
- I simply skipped all the bebe's in the TB hoses and since 2 hoses are between the TB and ECR valve I looped each back on itself and hooked on the factory mounts near the throttle linkage between each to look factory.
- I also used the same wiring harness posted in #45 which worked out great. The one issue I personally hit a wall on is I first added the 80 ohm resister that 619toy listed above but the only on I could find was a 25W monster that looked nothing like the others. I couldn't get the trigger to work so had to order a 100 ohm which I ended up still having an issue with due to my soldering skills so bypassed this and it worked perfect. The readiness came extremely quickly so I have no worries about the fluttering of the relay trigger. Especially due to the fact the relay is pulled when readiness is achieved. I'm not an electrical engineer and was showing voltage on both sides of the trigger so guessed the issue was the VSV was not grounding when triggered and almost started digging into it.
- After all reset I did the 4.7K resister on the temp probe by simply cutting the wire on the probe side of the connector and adding the resistor leaving everything in place yet looping the computer side and pushing into the factory heatshrink to get out of site.
- Last Item is I achieved readiness before clearing the last code with the check engine light on for some silly reason but after getting system readiness and the engine light cleared on its own I was still showing the P0401 code with readiness and no check engine light. I thought it was possibly my terrible scan tool I was using. I ended up going to get emissions rather than trying to go thru the whole process again. Even though showing this code they passed the emissions because the check engine light was functional and all systems were showing ready. Not sure if this is normal or the girl there doing me a favor? Seemed kind of silly since this seems to be the whole reason behind mandatory emissions testing here.
Last item, anyone in North Colorado the Fort Collins station off I-25 can now test vehicles with large tires so you wouldn't have to go thru all this nonsense anymore. You can test your emissions on the AWD system with no need to dig into your OBDII system.
Tried the harness modification last night. I had to use an 82 Ohm resistor on the Red/Yellow wire (that's all I had) instead of the 100 Ohm - it clicks a lot with throttle changes, but as it's temporary, I'm not too worried about it. The "rigging" worked like a charm. Drove about two miles before EGR readiness was achieved, cat readiness wasn't too far behind. Now to hack up the EGR temp sensor plug to install the other 4.7k Ohm resistor. Great work all around and thanks for keeping the schematic and other pictures uploaded.
One tip about the install, room is tight under the ECU, removing the dash bracing beneath the glove box helps a lot, just make sure you don't put vampire clips along the wires where they rest against the brace, there won't be enough room.
One tip about the install, room is tight under the ECU, removing the dash bracing beneath the glove box helps a lot, just make sure you don't put vampire clips along the wires where they rest against the brace, there won't be enough room.
So i have about 40 miles and started with 2 Incomplete readiness now have 1 so the relay helped. SHould I keep driving it. Others seem to achieve readiness within a few minutes. I have my EGR hoses plugged and the EGR Temp sensor hooked up as it would be stock. Should I put the 4.7kOhm resistor on the EGR Temp sensor?
gents, @SuperHatch, @AppleTech
i've got a 97 lx 450 studying these threads as i try to solve a p0401 EEC code in the hopes of getting inspected and registered with new plates. right now i am looking at the "resistor mod".
the issue i am having is this "readiness state" apparently not being recoverable after doing the resistor mod when you already have an error code? i'd like to retain readiness. actually i'd really like to retain readiness. but if i do the mod i will lose readiness i guess and i am concerned i am not going to be able to follow these step.
is there a plug in type product that could be produced to help some of us noobs with this? something that could be sold? is there a more concise write up that would make it easier for some of us? i'm having a hard time following a lot of this i have to admit. anything that could be put together that we could pass around and share?!
just trying to get a handle on this but feeling like i need to get an electrical engineering degree to not mess it up.
thansk for any help.
- jonathan
i've got a 97 lx 450 studying these threads as i try to solve a p0401 EEC code in the hopes of getting inspected and registered with new plates. right now i am looking at the "resistor mod".
the issue i am having is this "readiness state" apparently not being recoverable after doing the resistor mod when you already have an error code? i'd like to retain readiness. actually i'd really like to retain readiness. but if i do the mod i will lose readiness i guess and i am concerned i am not going to be able to follow these step.
is there a plug in type product that could be produced to help some of us noobs with this? something that could be sold? is there a more concise write up that would make it easier for some of us? i'm having a hard time following a lot of this i have to admit. anything that could be put together that we could pass around and share?!
just trying to get a handle on this but feeling like i need to get an electrical engineering degree to not mess it up.
thansk for any help.
- jonathan
so if a human "I" live in a state that doesn't care about human life in general and there's no need to comply, readiness is a non issue? is this correct. "readiness" is just to fool some government equipment into thinking you are compliant. and has no effect on the motor?
Not sure your state, but CO was fine with that code, as long as the limits were maintained, at least on a 97'
LC4LIFE
Supporting Vendor
Generally speaking readiness simply means that the ECM has made it through enough drive cycles to insure there are no issues with the motor to throw codes. It all depends on the code preventing readiness, but in regards to the EGR codes, not having readiness will have no ill effect on the motor.
The code is cleared prior to adding the relay. Once readiness is achieved, you install the resistor so the ECU believes the EGR is working normally - no codes to cause concern at inspection. The mod worked great on my 97 and I passed emissions in Davidson county, TN.
