I'm using a DEI 555h immobilizer bypass module for a remote start, and randomly it decides not to send the key code to the ecu. It will work 5-10 times, then not work once or twice, and then it will work again. I have tried reprogramming, but I still get the same result. The car starts with the key everytime, so a wiring problem can be ruled out, as the code from the key goes through the 555h. How likely is it that I have a faulty unit? I'm open for any other tips/suggestions.

 

Where do you have the 555H mounted? I had the same problem with one before and it turned out that I mounted it where it was exposed to too much heat and that would cause it to work intermittenly.

 

Behind the gauge cluster. I don't think that heat is the problem. I had the car sitting outside for a few hours, and it started right up. Then I put the car in the garage (evening, so it was cooler) for a couple of hours, and then it wouldn't start. I'll try relocating it though. Hopefully that will help.

 

Try to relocate it as close to the ignition as possible. That's what I did and it hasn't given me a problem. I think that since it's an RF signal it needs to be as close as possible to the ignition.

 

The only rf signal is from the key, which is picked up by the detector around the ignition switch. The rest is all digital signals. I don't see how that would make a difference. Maybe I'm getting interference in the signal, but if that were so, then the signal from the key would work intermittently also. Either way I look at it, it doesn't make sense.

 

last one i put in wouldn't work at all. i called dei techsupport 5 times. all 5 times they verified everything was right. we finally came to the conclusion to use a 556u.......worked like a champ.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by JSPECSIR &raquo;</TD></TR><TR><TD CLASS="quote">last one i put in wouldn't work at all</TD></TR></TABLE>

That's different, because mine works. The only problem is that once in a while it doesn't send the code. I'm not gonna switch to the 555u just because of that. I'll try to relocate it tomorrow and see if that helps any.

 

Sounds to me like a problem in the unit itself, it has to be 1 of 3 things...

1- Remote start is intermittently not sending the "ground out when running" signal.

2- The wiring of the 555H is poorly done, and there is an intermittent problem.

3- There is a problem with the 555H.

If you have checked your wiring and it's good, [it must be wired properly for it to work at all] but if you are sure all the connections are good, then you can eliminate 2 as the problem, that leaves 1 and 3, to check one, you can meter the output of the remote starts "ground out when running" lead with a meter when the bypass is not working or just connect, [parallel] a lead to the "ground when running" input to the 555H and have it easily accessible to ground the next time it will not start, the remote start should try 3 times to start the car, if it does not start the first time ground the lead, if it does start when you do that then you know the problem is in the remote start, if it still will not start you know the problem is in the 555H and it needs replacing, it comes with a 1 year warranty, [if purchased from an authorized DEI dealer. 94

 

the 555h has problems working with all honda's
try the 556h but you will lose your spare key!

 

we stopped using the 555h at my work we just use 556u's. ull just have to deal with losing a key if u want reliability.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by fcm &raquo;</TD></TR><TR><TD CLASS="quote">Sounds to me like a problem in the unit itself, it has to be 1 of 3 things...

1- Remote start is intermittently not sending the "ground out when running" signal.

2- The wiring of the 555H is poorly done, and there is an intermittent problem.

3- There is a problem with the 555H.</TD></TR></TABLE>

1. I have the unit trigger connected to the starter relay, and the starter turns on every time, so this can be eliminated. By the way, the RS is a homemade unit.
2. All the wiring is soldered. The key works everytime (key code goes through the unit). When the unit fails to send the code, I'll try to restart usually within 10-20 secs, and then it works fine.
3. I had the unit tied to a wire harness behind the cluster. I moved the unit away from the wire harness, and so far, 2 successful starts. Give me a few more days, and I'll see how it goes.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SRCRX &raquo;</TD></TR><TR><TD CLASS="quote">the 555h has problems working with all honda's</TD></TR></TABLE>

Looks like someone didn't read the whole thread. I got the 555h to learn my key code without a problem.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by incubus &raquo;</TD></TR><TR><TD CLASS="quote">ull just have to deal with losing a key if u want reliability.</TD></TR></TABLE>

So are you saying that the 555h is not reliable or are you referring to the problem where it does not want to learn a key code?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by incubus &raquo;</TD></TR><TR><TD CLASS="quote">we stopped using the 555h at my work we just use 556u's. ull just have to deal with losing a key if u want reliability.</TD></TR></TABLE>
my boss did the same thing.

 

I checked with the install supervisors in our other stores and they indicate that the 555H has reliability problems and they prefer to use the 555U or make there own bypass.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 02 accord &raquo;</TD></TR><TR><TD CLASS="quote">

1. I have the unit trigger connected to the starter relay, and the starter turns on every time, so this can be eliminated. By the way, the RS is a homemade unit.
</TD></TR></TABLE> What do you mean "homemade"? I was speaking of the unit's ground out when running lead, what do you have connected to the 555H ground trigger input, how is it activated? 94

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by fcm &raquo;</TD></TR><TR><TD CLASS="quote">What do you mean "homemade"?</TD></TR></TABLE>

Don't you know what homemade means? I got bored one day, and decided to take on this project.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote &raquo;</TD></TR><TR><TD CLASS="quote">what do you have connected to the 555H ground trigger input, how is it activated? 94</TD></TR></TABLE>

I have the starter relay connected to 12v, and when I remote start, I switch the ground to the relay. I do likewise to the 555h. At the same time, the ignition also turns on.

My RS circuit works fine. Only sometimes, everything turns on like it's supposed to (including the starter), but the immobilizer key on the cluster flashes, indicating that the ecu did not receive the correct code. This will happen usually once (once I had it do that twice in a row), and almost immediately after that, the car would start normally (using RS). As I said before, give me a few more days, and I'll see if it still acts up.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 02 accord &raquo;</TD></TR><TR><TD CLASS="quote">Don't you know what homemade means? </TD></TR></TABLE> Well Daaa! I assume you made it yourself, maybe even at home, I was looking for some detail, like what is being used for the RF, an alarm, key-less or was it "homemade" also?

If everything is working as it's supposed to except the 555H, then it's a good bet the 555H is the problem, [as has been mentioned] do you understand? 94

 

For RF, I'm using the factory keyless (alarm) remote. To activate remote start, you have to press lock, unlock, trunk release, in that order all within ~10 second time frame. During that time, the car stays locked and the trunk does not open. It's a simple unit that assumes that the engine starts everytime (doesn't try to restart).

 

^ Now I'm very curious. Any chance you've done a write up? I have a buddy who would be very interested in this

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by a_s_ol_ &raquo;</TD></TR><TR><TD CLASS="quote">^ Now I'm very curious. Any chance you've done a write up? I have a buddy who would be very interested in this </TD></TR></TABLE>

No writeup. I'm not a fan of step-by-step instructions anyway. Plus, I don't think it's gonna be worth the effort. I was using whatever parts I found around the house (including 555 timers, caps, resistors, relays, relay driver IC). For me, this project was cost efficient, because I had most of the parts laying around (from amplifiers, monitors). To buy all those parts would cost more than buying a ready-made RS unit. And then you would still have to put in a lot of work to put the unit together.

My next planned project is a full alarm system with tilt/shock/motion sensors, probably control of each door's power lock/window, remote start (of course), a long range remote (still gotta figure out this part), and maybe gps tracking. First I gotta figure out the remote to see if I can integrate gps into it. If that works out, I might design a stand-alone remote start unit controlled by a microprocessor (less parts, more control). If I end up doing that, I will post a writeup.

 

Got some updates. I replaced the bypass unit with another 555h: same problem. First time I wired it, I left all the wires full-length. This time, I cut off over a foot from the signal wires (now they're about a foot long)...Same problem. I programmed a different key: same problem. I don't know what to do with it anymore. I can live with it, but it's starting to **** me off.

 

What is the blue wire, [of the 555H] "status input" connected to? 94

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 02 accord &raquo;</TD></TR><TR><TD CLASS="quote">I have the unit trigger connected to the starter relay, and the starter turns on every time</TD></TR></TABLE>

 

The starter relay is 12V+ output, is it not and the 555Hs status input is 12V-, also I believe the bypass needs to be activated first, as it would if you just use the key, maybe that's the problem, the 555H is not activated until after ign. is on and not until starter is engaged. 94

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by fcm &raquo;</TD></TR><TR><TD CLASS="quote">The starter relay is 12V+ output, is it not and the 555Hs status input is 12V-, also I believe the bypass needs to be activated first, as it would if you just use the key, maybe that's the problem, the 555H is not activated until after ign. is on and not until starter is engaged. 94</TD></TR></TABLE>

I should've said this in the last post. The starter relay is constantly connected to +12, and I'm switching the ground to it and to the 555h. Everything turns on at once (ign, 555h, and starter).

I've played around with the timing of the 555h, and it needs to be activated when the ignition is turned on. Anything later than that, and the ecu will not accept the code.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 02 accord &raquo;</TD></TR><TR><TD CLASS="quote">

I should've said this in the last post. The starter relay is constantly connected to +12, and I'm switching the ground to it and to the 555h. Everything turns on at once (ign, 555h, and starter).

I've played around with the timing of the 555h, and it needs to be activated when the ignition is turned on. Anything later than that, and the ecu will not accept the code.</TD></TR></TABLE> That's what I mean, [timing] have you tried triggering the 555H before ign. comes on, I have not run into the exact same problem as you are having with the 555H, but I have run into ones that do not work at all and ones that are intermittent, [although, intermittent to what %age, I don't know, we just replace them if they mess up in any way] but I do know they work best when they are triggered, with a good ground, before ign. is on, that may also be dependent upon MM&Y of the car, [year and type of OEM immobilizer system] just a thought. 94

 

This is really weird. After having programmed a different key, it didn't work a couple of times, but after that, it's been good to me. I guess I'll just live with it until I put in a full alarm with remote start/rpm sensing.