Electrical alarm issue

[Lankstarr]

A bit of a long shot that anyone knows what's going on with my alarm but here goes:

Toad AI606 installed for 3 years.
Recently the immobiliser is giving me grief and preventing me from starting the car.
All electrics in the car work fine.
If I have the problem then jumping the car will make it start.
Battery has been checked out and is fine.
Honda diagnosed a dodgy connection on the positive battery terminal; I've taken it apart, cleaned it and bulked it out with tinfoil to ensure a tight connection.
No problems with any electrics or power, just the immobiliser.
Playing around with the battery terminal, taking it off and putting it back on helps resolve the issue - car starts on third attempt after doing this (has both times I tried it).
No problems starting the car once it's started once... apart from when I get back to her after work (got me once when I was late getting home!).

Alarm guy says it is the door connection and that I need new sensors - the car should start regardless of whether the door is open or shut so I think he fobbed me off. He said that jumping the car would send a surge to the door sensor and that's why it worked when I jumped it... again I think he's a good bull-shi77er!

Any ideas would be greatly appreciated - playing around with a greasy battery at 7am in my suit is not the best start to the day!

Thanks,

Luke

[NSXGB]

I'm no expert, but a couple of observations...

Tin foil - sounds like a bit of a bodge reair to me. You can buy a new battery terminal and fix that to cancel that out from the equation.

You say that the car starts after the third attempt? Has it always been that way? Mine always starts on the button, first go every time. Do you let the fuel pump prime before you crank? That may be nothing to do with your immobiliser problem but may point to another starting issue.

[WhyOne?]

You say that the car starts after the third attempt? Has it always been that way? Mine always starts on the button, first go every time. Do you let the fuel pump prime before you crank? That may be nothing to do with your immobiliser problem but may point to another starting issue.


I am no expert either but for the car to only start at the 3rd attempt sounds odd to me - is this the norm?

[Silver Surfer]

Battery power not enough?? Starter motor a bit stiff?? :dunno:

SS

[Lankstarr]

I am no expert either but for the car to only start at the 3rd attempt sounds odd to me - is this the norm?

I probably shouldnt; have written about the third time as I think it's a bit of a red herring! I've never had trouble with the car starting until this passed week - twice I've removed the battery terminal, had a scratch around inside and refitted. After performing this the car started on the third try - the immobiliser preventing it from starting the other two times. Once it's started it fires up every time I stop and start it ... first time.

The battery has been checked out for power and it's fine - although the fact that it works (first time) with a set of jump leads attached is confusing. for some reason sticking a few extra volts through the circuit helps.

When I turn the key and it doesn't work I get a click; the same click I get when the immobiliser from the alarm needs disarming and nothing like the click you get when you have a flat battery.

Starter motor... possibly but I have no idea what impact this would have and whether it would be tempremental or just break. If I didn't have the alarm I'm sure it would be fine! I'm thinking about disabling the alarm so I don't get stuck anywhere; if the problem recurs then at least I can rule out the alarm. Just need to find the book and work out how to disable the darn thing!

I know the tin foil is a temporary fix but the connection isn't too bad and it is just there to try and rule it out... I'll check the voltmeter but pretty sure it's not showing any power down.

thanks,

Luke

[NSXGB]

When I turn the key and it doesn't work I get a click; the same click I get when the immobiliser from the alarm needs disarming and nothing like the click you get when you have a flat battery.

thanks,

Luke

Is this a different click to the fuel pump relay 'click', i.e. the click you get when the ECL goes out?
I don't think you should get any clicks from the immobiliser, although I've never had a TOAD alarm....

If you can disable the alarm, this will eliminate whether it is definitely part of the problem.

A dry joint in the main relay is a common fault that can give starting problems IIRC.

[Kaz-kzukNA1]

Hi, Luke.

I think you already found one of the possible solutions – disabling the alarm circuit.

As I don’t know the year model, MT/AT, how the Toad system was installed and without looking at your car, I could be wrong but I hope following information will help you.

I have the Toad system on my other car (as you know from our previous PM).

1. Battery
How old is your battery? I know your car is used everyday and you didn’t experience any issues until recently but just wanted to check as I don’t know how the battery was tested. Was it load tested or just measured the voltage? I’ll leave the ACG charge circuit at this stage.

By the way, if it is safe to do so, it may worth testing the following.
Keep the car in the safe place and leave it over the night without arming the Toad system. If you managed to start the engine, it would be more likely to be Toad system related. If you still have the same issue, then there are other issues than the Toad system unless you have failure inside the Toad control unit or the immobiliser wiring.

2. GND cable/terminal
As in your post, you mentioned about the state of battery Positive terminal. How is your Negative terminal and GND cable? Did you feel any loose connection or give a good clean on the negative side as well?

3. OEM security and Toad system
Do you have OEM security system and the Toad one? Or, is your car the early model that it didn’t come with OEM security system?

4. Toad system
Once the system is disarmed, the door switch doesn’t play any role in the immobiliser circuit. As you stated, you can start the engine with door opened/closed.

The Toad control unit will act as the switch to open/close the connection where the immobiliser circuit was inserted. There are a few immobiliser circuits (I’m not going to write down the exact number) within the control unit and there are a few places (again, I’m not going to write down the exact locations) on our car that we can use for the immobiliser purpose.

Therefore, once you managed to disarm the Toad system with the key hob, unless the control unit or wiring connection has a problem, you should be able to engage the starter at least. I was quite interested in the following comment;

.... I've never had trouble with the car starting until this passed week - twice I've removed the battery terminal, had a scratch around inside and refitted. After performing this the car started on the third try - the immobiliser preventing it from starting the other two times. Once it's started it fires up every time I stop and start it ... first time.

This suggested that the voltage of the IGN line connected to the Toad control unit dropped but I’ll touch on this in the ‘LED’ section.

If you want to bypass the Toad system for your investigation, you need to know the exact connection points to bypass the cables. Simply removing the Toad control unit won’t work. As you seem to know the Toad system installer, you should be able to ask him/her. Not easy to bypass the cables though as this is the whole point of immobiliser.

Alternatively, you can try another Toad control unit by borrowing it from the installer or you can try mine:).

5. Toad LED
If the Toad system is preventing you from starting the engine, the status LED will show you solid Red when the key is in ‘ON’ position.

If the system was disarmed properly, the LED will be switched OFF when the key is in ‘ON’ position.

If you try to arm the system with any of the sensors such as door, bonnet, boot, etc open, the siren and the side indicator will trigger 3 times. If the immobiliser was triggered after you arm the system, the first time when you turn the key to ‘ON’ position, the LED will show number of Orange flashes to indicate the cause of trigger. This will include the condition that someone tried to tamper with the battery or the ignition line.

6. AT inhibitor switch
I don’t know the year model, AT or MT of your car but I know a few issues reported with the AT inhibitor sw on the earlier models.
It is at the side of AT shift gate and detects the position of the lever. Unless in P or N position, you can’t crank the engine.
Later models including MT have extra inhibitor switches to prevent the engine from cranking.

7. Main relay
As NSXGB mentioned, please replace your main relay if you haven’t done so.
Keep the existing one somewhere on your car as an emergency spare for someone else. I already saved 1 NSX owner with my old one. Please note that the parts no. is different for the later model.

8. 'Click' sound
This all depends on how the immobiliser circuits were inserted into your OEM cables. You may hear it or not at all.


If you can’t solve the issue, send me an email as you can try my Toad Control unit and I’m more than happy to look at your car. Also, I can look at your CCU at the same time.

Regards,
Kaz

[Lankstarr]

Hi Kaz,

The comprehensiveness of your replies always puts a smile on my face - thanks!

FYI my car is a '98 manual and the alarm was professionally installed.

1.
The battery is about 2 years old. When Honda servicde the car last time they said teh battery needed replacing, I told them it was little over a year old and they backed off a bit (think they may have been trying it on!). I asked them to retest it following initial occurance of this problem and they said it was fine. It is the correct battery for the NSX.

I managed to start fine (first time) this morning and last night on my way home... it does make me nervous walking to the car though! I went into the car via the passenger door (after the alarm fitter making me paranoid about door sensors!) ... maybe that had something to do with it starting!? Hard to tell unless I repeat for several days. When I have the problem I've tried shutting the car up, alarming it and then going in through the passenger door once I've disarmed... no joy as once it decides it won't start it's pretty stubborn!

It's safe to leave the car unalarmed, but the immobiliser kicks in after 20 seconds or so anyway. I'll have to check the book on how to temporarily disable it or put it into some sort of valet mode. I'll try and just not arm it anyway, maybe it's part of the control box or something like you say. Hard to diagnose a tempramental problem!

2.
I checked the tightness of the negative terminal but didn't take it off for a good clean - I will try this.

3.
My car is the later model with the OEM immobiliser; I hadn't really considered that it may be this immobiliser that's causiong the problems but I guess trying the spare key next time it happens may help to diagnose this.
Funny thing is that after I installed the cat 1 alarm I called the insurance company to tell them and they didn't care as it already had an OEM immobiliser - if they don't care then I guess it was a waste of money (especially now if it is the cause of my grief)!

4.
If the alarm is looking like the problem then I guess I come back to this point and thanks for your offer of the control unit. I suppose swapping control units should be simple once I've located it, I thought I cuold just switch the alarm off completely for my investigation but maybe not!

I know my installer but he's a lazy git and likes fobbing me off where possible!

5.
I'm pretty sure the light was off when I tried to start the car; I'll make sure again when it happens and note down the exact sequence of colours and flashing.

Reading again I'm 99% sure the light wasn't red and that I didn't get any flashes when I have been arming and disarming. Certainly there have been no beeps!

6.
Does being a '98 manual mean I have extra inhibitor switches!?

7.
The main relay is original, is this a cheap relay from Honda or some sort of main, more expensive relay!? It sounds like it's worth replacing but as my car is '98 maybe it's not old enough yet for it to be an issue!?

8.
I'm not sure whether my click sound is OEM or Toad clicky now!

I'm nearly out of the timeframe that requires demisting every morning so may well give you a visit to deliver the circuit board. I'll try to rule out a couple of things in the mean time and let you know how I get on. the problem with this problem is that it is tempramental so I don;t know how to reproduce it for demonstration!

My last alarm issue hasn;t recurred very frequently and only occurs outside my house (the probnlem is that it doesn't disarm!). If I trip the main switch to turn off all of the electrics in the house then it starts fine:eek: I've tried a few obviously electrical things but with no luck; I need to trip the whole switch in order to get it to work. Again it doesn't happen often (I don't think it's happened yet this year... or maybe once) so it's hard to diagnose. When these things sdo happen I'm usually on my way to work so don't have time to get stuck in and play or try different things.

Thanks again for your help Kaz:)

Luke




Hi, Luke.

I think you already found one of the possible solutions – disabling the alarm circuit.

As I don’t know the year model, MT/AT, how the Toad system was installed and without looking at your car, I could be wrong but I hope following information will help you.

I have the Toad system on my other car (as you know from our previous PM).

1. Battery
How old is your battery? I know your car is used everyday and you didn’t experience any issues until recently but just wanted to check as I don’t know how the battery was tested. Was it load tested or just measured the voltage? I’ll leave the ACG charge circuit at this stage.

By the way, if it is safe to do so, it may worth testing the following.
Keep the car in the safe place and leave it over the night without arming the Toad system. If you managed to start the engine, it would be more likely to be Toad system related. If you still have the same issue, then there are other issues than the Toad system unless you have failure inside the Toad control unit or the immobiliser wiring.

2. GND cable/terminal
As in your post, you mentioned about the state of battery Positive terminal. How is your Negative terminal and GND cable? Did you feel any loose connection or give a good clean on the negative side as well?

3. OEM security and Toad system
Do you have OEM security system and the Toad one? Or, is your car the early model that it didn’t come with OEM security system?

4. Toad system
Once the system is disarmed, the door switch doesn’t play any role in the immobiliser circuit. As you stated, you can start the engine with door opened/closed.

The Toad control unit will act as the switch to open/close the connection where the immobiliser circuit was inserted. There are a few immobiliser circuits (I’m not going to write down the exact number) within the control unit and there are a few places (again, I’m not going to write down the exact locations) on our car that we can use for the immobiliser purpose.

Therefore, once you managed to disarm the Toad system with the key hob, unless the control unit or wiring connection has a problem, you should be able to engage the starter at least. I was quite interested in the following comment;


This suggested that the voltage of the IGN line connected to the Toad control unit dropped but I’ll touch on this in the ‘LED’ section.

If you want to bypass the Toad system for your investigation, you need to know the exact connection points to bypass the cables. Simply removing the Toad control unit won’t work. As you seem to know the Toad system installer, you should be able to ask him/her. Not easy to bypass the cables though as this is the whole point of immobiliser.

Alternatively, you can try another Toad control unit by borrowing it from the installer or you can try mine:).

5. Toad LED
If the Toad system is preventing you from starting the engine, the status LED will show you solid Red when the key is in ‘ON’ position.

If the system was disarmed properly, the LED will be switched OFF when the key is in ‘ON’ position.

If you try to arm the system with any of the sensors such as door, bonnet, boot, etc open, the siren and the side indicator will trigger 3 times. If the immobiliser was triggered after you arm the system, the first time when you turn the key to ‘ON’ position, the LED will show number of Orange flashes to indicate the cause of trigger. This will include the condition that someone tried to tamper with the battery or the ignition line.

6. AT inhibitor switch
I don’t know the year model, AT or MT of your car but I know a few issues reported with the AT inhibitor sw on the earlier models.
It is at the side of AT shift gate and detects the position of the lever. Unless in P or N position, you can’t crank the engine.
Later models including MT have extra inhibitor switches to prevent the engine from cranking.

7. Main relay
As NSXGB mentioned, please replace your main relay if you haven’t done so.
Keep the existing one somewhere on your car as an emergency spare for someone else. I already saved 1 NSX owner with my old one. Please note that the parts no. is different for the later model.

8. 'Click' sound
This all depends on how the immobiliser circuits were inserted into your OEM cables. You may hear it or not at all.


If you can’t solve the issue, send me an email as you can try my Toad Control unit and I’m more than happy to look at your car. Also, I can look at your CCU at the same time.

Regards,
Kaz

[Lankstarr]

Is this a different click to the fuel pump relay 'click', i.e. the click you get when the ECL goes out?
I don't think you should get any clicks from the immobiliser, although I've never had a TOAD alarm....

If you can disable the alarm, this will eliminate whether it is definitely part of the problem.

A dry joint in the main relay is a common fault that can give starting problems IIRC.

Hi Simon,

What's the ECL!?

Maybe I'm looking at an OEM problem and should focus my efforts here - main relay definitely sounds like the first place to look - thanks.

I'm going to get greased up for some window action so will be contacting ~Honda for some lubey ... any idea what the part number is for the main relay and how much it is... if it's reasonable then I'm probably best just going to Honda.

Thanks,

Luke