VCANTU

2000 Acura RL

Originally I was sure the immobilizer went bad, bought a new one installed it but it needs to be programmed to the car keys. My friend from Honda came with his HDS computer and connected it to the DLC behind the ash tray but it did not detect anything. Meaning it did not find an ECU. My friend thought it was the ECU or the main computer. He got another computer, known to be good, but same thing, the ECU did not get detected.

I need some help here. What could be causing the no detection of the ECU?
Anyone had such an experience?

Thanks for your help.

Megatron

I think first you need to see if any regular OBDII scanner will power up on your port. Do you have any friends or have access to a normal cheapo OBDII reader? That will tell you if it's a power issue and ALSO tell you if your computer is talking at all.

Let us know what happens after that test!

VCANTU

Actually today he was trying a hand held scanner. I shouldn't have said HDS computer.
The little scanner did not detect a ECU.
Would there be an online fuse or something that is preventing the ECU to power up. Of maybe some componet of the immobilizer system is not permitting the ECU to power up. Like maybe the "antenna" on the key cylinder.
Do you know if the ECU independant of other modules or controls?

Thanks for your input..

Megatron

So the scanner powered up off the OBDII port? That would mean you are getting power off the port. Is the scanner coming on and then it scans for the car computer, but comes back with nothing? What is the exact error message you get??

And the key is ON and all the dash lights are on while you are scanning right?

pdbailey

If it gets power from the port, then there will be a reference/ground pin and a +12V pin you should be able to get the pin outs online and just use a VOM to check for power.

VCANTU

Megatron,
I was only watching the tech plug in the hand held scanner onto the port. He did turn on the key. The display of the scanner was lit (not sure if it was because of the port power) but it would not come up with the detection of the ECU.
On the prior attempts, days back, the tech had the other computer, the HDS, and I did see on its screen displaying "WAITING" and then it would not display nothing. The tech would just say, "it is not detecting the ECU". That the ECU was fried. Now after he replaced it with a new one the exact same thing happened. Although he was just plugging in the hand held scanner.
This last time the car has a new Immobilizer and a new ECU. The tech is saying that the Green Key Light is not even being lit at all upon turning the key on. That is should blink and stay blinking since the immobilizer has not been programmed. So one question is;what changed from the original problem. The original problem was that the Green Key Light was not coming on and therefore the car was not starting. So I replaced the immobilizer and stilll no Green Key Light. Then the tech comes to program the immobilizer but since there was no light he plugs in the HDS to check out the system and that is when it would not detect the ECU. So the next day he tries a hand held scanner and same thing, no detection of the ECU.
Then the next thing was replacing the ECU but nothing and that is where I am at right now. The tech is suppossed to print a wiring diagram to trace the wiring.

I wonder if there is some unit in between the port and ECU that is fried or a wire that is making contact with something else that is the being culprit????

Thanks to all for your input.

VCANTU

I have the manual and I remember reading what all the pins on the ECU connectors show read. Actually the wire side of the connector and it states to check for certain voltage with the key on or off.

Thanks PDBAILEY for your input..

Megatron

Based on what you said here, are you saying the ORIGINAL problem (before you swapped any parts) was that the green key on the dash never came on when you turned the car on?? If it had been an immobilzer problem, the green key would have come on and then stayed blinking. That is the sign of an immobilizer authentication problem. If you didn't even have a blinking green originally (before you swapped anything), I would have told you then that it was NOT an immobilizer problem, and likely something else in the electrical or computer or starter.

VCANTU

I searched online about the green light not coming on and therefore the car not starting. The messages I read were all pointing to a bad immobilizer unit. That is why I replaced it. Now that being replaced, the still no green light came on at all.
Before replacing the "bad" immobilizer, the car would just die while driving it. It did it three times and then I just left it parked in my garage. The first time it was riding fine and then I pulled over to a starbucks, walked in and got a coffee, came out and started the car to find out it wouldn't start. No green light. Forty minutes later Triple A came and towed my car to my house, and before pushing it into the garage the tow truck driver thought of crancking it again and it started fine.
The next time it died while driving it. The green light would not come on. I thought it would not start so I called Triple A. After waiting 10 minutes I thought of turning the key and I saw the green light come and then off, I felt I am good to go and the car started. Same thing happened on the third time. Then i thought of just parking it in the garage because I could not trust it anymore. That is when I started searching for the problem and I got lead to the immobilizer being the problem. Replaced it and my friend was going to program it but he saw that there was no green light and connected his diagnosting computer to the DLC but there was no communication with the ECU.

Thanks for you input...

Megatron

AHHH!!! Now we get more info! The immobilizer would NEVER be the cause of a car dying while running. Once the car is started, the immobilizer is out of the picture. If you broke the end of the key off in the ignition so the head of the key was removed and thrown out of the car, the car would still be running. The immobilizer is ONLY involved in the actual startup of the car.

So your problem of the car dying all of a sudden has nothing to do with the immobilizer. The car not starting after you shut it off MIGHT be, but I would guess that instead of the immobilizer, it would have something to do whatever was causing your car to die while running. The no green light at all is another clue that it's not the immobilizer. Bad immobilizer detection would result in a flashing green, not no green at all.

Did you happen to connect any scan tool to the car PRIOR to swapping out anything? Meaning with original ECU and original immobilizer? I wonder if a scan tool would have detected the computer before you did any of the component swap. That would determine whether any of the new parts is causing the problem with not detecting anything with a scanner.

VCANTU

It is all making sense now....
I did not connect a computer to this car in a long time. One time I took in to the dealer for a SRS light staying on. There was a recall and Acura replaced a unit that goes behing the passenger seat. That was a couple of years back. But it was working fine with a rare incident like the one presently going through. This time it was happening more frequently so I parked to resolve the issue.

After a few days without doing anything to it and after coming back from a camping trip on Sunday night I decided to do some checking from the immobilizer wire connector. The manual intructs to look for continuity and power voltage on the wire side of the connector. Most of the wires showed readings as described in the manual except a couple of them did not. Then I was going to move on to the connectors on the ECU end when I pressed on the brake pedal with the key on III and I hear a solenoid or something that releases the shift stick to move freely between gears. I thought that is different, that is normal I thought, and then I looked at the green key light and I see it is on..and I get excited because these are signs of my car is ready to start. Now I am thinking that the ECU is also going to be detected by an HDS computer. I tried cranking the engine to see if it what it would do but after turning the key there was absolutely nothing, no engine turning, nothing. Just the panel keys where on. But then I thought that the keys have not been programmed to the immobilizer unit and maybe that is the reason why it did not turn. Also it has a new computer, I don't know if that has to do anything with it not turning. I would think that it would do the same as when there is no green light, the engine does turn but it just doesn't start. ?????
When doing the connector wire checks I ran on to a suggestion that the shift placement switch might be faulty. Would that sound like the reason for the car dying?

Still one mysterious thing is why would the computer not be detected by HDS..as if there was none existing in the car? And if it is detected now, what is causing that intermittent on and off of the ECU. I think that is the one that is making the car die, the ECU. But why is a new ECU doing the same thing? Could it be a grounding problem?

I called my friend at Honda to tell him that the car now has the green key light blinking and I am almost sure the ECU is working again. He said he can come by today and try connecting the computer again.

Megatron can you please email me a new code for today?

I hope all this helps in detecting the problem. I will keep posting until the problem is solved.

Megatron

After reading all this, I still don't get what you did to get the blinking green key back? Maybe I missed something? What exactly did you do to get the green blinking key to come on again?

As for the engine not cranking, it is perfectly normal on your RL to not crank when the immobilizer doesn't detect a programmed key. The dash should blink the green key and if that is the case, no cranking will occur at all (it's not a crank but no start... it is NO cranking at all!).

I don't know about that brake switch and shift thing. There is no reason why any faulty brake switch would cause the car to die. The switch that causes the shift knob to unlock and allow you to shift is that same switch that turns on your brake lights. It makes no sense that if your switch is bad, that your car would die... maybe on one of those newer cars with the engine stop at every red light it would make sense, but not on your RL.

VCANTU

I don't know what I did to get the Green Key Light to come back on. But it has been acting normal under the circumstances.

Just now I have decided to risk it and losing that gain again. I have placed back the old ECU and the old immobilizer unit and tried starting the car. To my surprise the car has started normal.....I am so exited to hear my car on again. So everything is back to how it was when it died while driving. So now I know the immobilizer is not the problem, nor is the ECU.
So now the question is what is making my car die while on the road? After the car died on the road, I saw that the Green Light would not come on at all. Now I am thinking that most likely the ECU would not be detected. I am thinking that what ever it is is cutting power to the ECU and therefore the immobilizer does not work. I am back to square one. I am going to see if I can take it to my friend so he can scope it out with the HDS. Hopefully HDS will detect the ECU this time.
Now that it is back to starting, I see that the "Check Engine" light is on solid. Could it be that it just needs me to drive it for a while?

It can't be the fuel pump because I can hear it come on after I turn the key.

What else is in the middle here? Is there an igniter?

I'm going to be brave and drive it to work tomorrow.

Nonetheless this is all too weird.....

VCANTU

I just finished putting my car back together. It has all the original parts, nothing was replaced and yet it starts on and idles smoothly. I am hesitant to drive it out because I don't trust it anymore. I'm afraid it will leave me stranded somewhere. I will wait for my friend to swing by my house with his HDS computer and see if it reports any problem.

I have read of some members reporting that their problems had to do with the MAIN RELAY, others reported that it was the IGNITION SWITCH.

I think what's happening here is that the power is being cut off to the ECU while driving. What interrupts power to the ECU? Could it be the MAIN RELAY or the IGNITION SWITCH?

We'll see what the HDS diagnostic says in a couple of days.....

VCANTU

Soon after my last post, I had my car diagnosed and it was all good. I had been driving my car normally since until this past weekend. Went into a store came back out and started the car and it would turn but not start. I looked for the green key light up on the cluster and it was not lit. I pulled out the Main Relay little box under the steering column and took it apart, while exposed I plugged it back on. While I was squeezing it with my fingers I turned the key, the green key light would be flickering on and off. Luckily I got it to remain on, the car started and I was able to drive home. I then determined that I needed to resolder the tips of the electronic components on that circuit board. I did and now it has been working fine again. Hope this experience helps others with this kind of a problem with the Acura's.
Thanks to those who helped....

THUBB

I know I am a little late, but I am having the same problem with a 2001 CL. Green key light doesn't come on and car only cranks, no start. There is a fuse on the passenger side under the hood labeled ACG S. it is a 15 amp fuse, and it was the only one busted. I replaced it and heard the fuel pump kick on while the key was forward. A few seconds later it busted the fuse. I put a 30 amp fuse and the key light came on and the car started like new! I just have to find out what is shorting the fuse out, but that is what is restricting my car from starting. Hope this helps guys

MyNameIsEarl

Not trying to be rude here, but certain amperage fuses are placed in the car for a good reason. It's to protect the electronics of whatever circuit it's on. If you have a circuit, say the one your fuel pump is on, which is designed to operate at 15 Amps, but you put a 30 A fuse on it, sooner or later your fuel pump circuit will be fried. Then you are going to have the worst time trying to find out where the entire circuit failed, and there are tons of wires, relays, boards, to check. Something is causing it to draw too much current. You could "solve" the problem at put a 1,000,000 AMP fuse on it and it would not blow. You are still risking your electronics either way.

Just a caution: don't put higher amperage fuses in places they don't belong.

THUBB

MyNameIsEarl, I am not planning on keeping a 30 amp, or 1,000,000 amp fuse in the place of a 15 amp fuse. I only did it to narrow down the problem and I actually found the problem doing this. I have done this same thing countless times on other cars and I have never "Fried" any electronics. If I were to continue to put only 15 amp fuses it would have just kept busting them every couple of seconds, not giving me time to find a hot or busted wire. I left the key forward for about 2min. and found the IAC (Idle Air Control) was shorting and causing the fuse to bust. Thanks for the advice but if you want to find the problem quick, sometimes doing things by the book isn't the right way to go.

Matt Mergenthal

Did anybody ever figure this out?

VCANTU

My problem was solved...
As I mentioned on my previous post here. The part that was giving me problems was the Main Relay unit. From what I read it is the soldering inside the unit that makes them fail. You can resolder them yourself and save some money.

Matt Mergenthal

I picked up that main relay from autozone and no luck

Taken Everafter

Ok so I know this post is pretty ancient but I'm having pretty much the same problem as the original post, just slightly different. My wife's ex had blown the engine in her '03 RSX Type S and her brother rebuilt it. After we got it back into the car and everything hooked up, and I called my wife out to the garage to hear it run for the first time in a little over a year (many rmany reasons as to why it took so long, luckily she has an '02 base model also to drive in the mean time) anyways. It fired up and ran for maybe 15 seconds and it just shut off like I turned the ignition off, which I hadn't. After that it wouldnt start, it would crank and crank with no start, also not hearing the fuel pump prime. Tested the fuel pump it works just fine. Then I noticed I had absolutely no immobilzer light. And I mean none. Did come on and constantly flash like i was using the wrong key and didnt come on for 2 seconds and shut off like I was using the right key, which I was. So I was thinking it was the immobilzer. I decided to hook up my obd key programmer another key just out of curiosity and noticed after I hooked my programmer up and turned the key, the immobilizer light come on like normal and the car started up just fine. So I shut it off. Unplugged my programmer and went to start it again. No immobilzer light and no start. Weird right? It gets even weirder. I then decided to disconnect the programmer its self from the obd cable and plug in the cable to the car only, so nothing on the tool end. Immobilizer light came on and started just fine. How could this cable be the solution to my problem I thought. So I was looking at the obd side of my cable and noticed there were 2 pins longer than any other, and i would get results from the car (meaning immo and start) as soon as the plug barely even touched the port. So it had to be those to pins jumping something that I needed I guess. Turned out that it was pins 4 and 5, being the chassis ground and the signal ground. So I took a small piece of wire and jumped those two on my obd port on the car and it worked! My immobilzer was working properly and starting and running perfect! So what I'm trying to figure out is why would it do this and how do I track the issue? Because I'm gonna guess and say it probably isn't okay to do?