5AS Wiring

[eaa53]

As the engine get close to installation, I have returned to the loom and the general wiring as I now have the donor loom on the floor so to speak.

The engine loom appears, with a bit of work a 'done deal' but the security module the 5AS is a black art with its TTL and DC signals as well as lots of wires that appear not to be detailed anywhere.

I have looked back in the threads for this detail but it appears that detail was passed between people off the forum.

Marlin do a 5AS loom I believe but I see no drawing detailed of the layout of the essential connections.

This web site may help if you are completely in the dark, it does not have the ABS circuits but does detail the internal wiring and operation of the 5AS the MFU(don't think we use this bit) and the VVC circuits. A wonderful piece of work to credit to the author.

http://homepage.swissonline.ch/TomsS...ation2/Map.htm

I would be interested in knowing if this is all I need to connect to get the engine running for more than 9 seconds at a time, once I get the point of trying that is...!






eaa53

[limpabit]

Hi John.

Steve (SDM..) some time ago, had the same problem. He did not end up using the Marlin loom. Maybe worth dropping Steve a PM to discuss.

[paulsul]

I was going to wire up the 5AS unit myself but thought better of it and bought the Marlin connection. It took a bit of head scratching to wire that up but it worked ok.
The imobiliser does not work though.

[eaa53]

To complete the detail I have, but not tested, so far....

Pin 1 Ignition supply (Dark green if memory serves)
Pin 2 Earth
Pin 9 Imobiliser signal to ECU pin 13 on my car.
Pin 10 Antena for remote signal.
Pin 23 Starter relay pin 2 (if remembered correctly this solves the problem with the starter just clicking)
Pin 26 Battery supply.

Here Pin 23 is added to the list of connections, there are other earth connections that are black wires that are not detailed also.

[technozen]

Hi John,
In response to your message on mg-rover.org here are two .xls spreadsheets that I made up which give the MFU and 5AS pinouts and descriptions.

Are you using a later type 5AS? It has two electrical connectors and will directly control the indicators to signal arm/disarm, it will also switch on the courtesy light on disarm.

Would it not be simpler to use the immobiliser activated by the fob?

Just shout if you need more 5AS/MFU info.

Paul

[eaa53]

Paul

I have the single plug 5AS unit from 1997.

Once I can download the files I am sure I will have some more questions.

Thank you for the effort you have made to join this forum to respond..

eaa53

[technozen]

No problem, glad to help.

I can also do programming/diagnostics on the 5AS and MEMS ecu's if you are stuck.

The later 5AS might solve a few of your problems due to the fact that it supports the indicator and courtesy lamp features.

[eaa53]

Paul

After reviewing your detail and comparing it to what I had it is clear that the single connector 5AS and the dual connector 5AS are very similar in functionality. There are differences but they appear to be interchangeable in basic operation. If you do not have the single connector pin out detail I can pass to you what I have.

I intend to use the donor FOB to immobilise the ECU remotely, I will mount the drivers door lock and key barrel to allow the key to be used to set the immobiliser and access the immobiliser override process if required. Do I need to make the motor active so the 5AS can see the lock(s) change state? I can to that very easily if needed, I can see I could potentially lock the clams if I wanted..

There are probably enough unused signals on the single socket 5AS to do what I want with external circuitry but it is time consuming to build and test.

So let me see if I have this correct; the single 5AS will:-

take the signal from the FOB and can lock/unlock the doors
activate/de-activate the immobiliser.
I suspect it can sound the horn if the security is compromised by one of the sensors (if they are connected).
I cannot see where the hazard warning lights are flashed for 'immobiliser/locked door activated' from the circuits I have including, the 1997 RAVE diagrams, are they activated from the MFU?

The dual connector 5AS will do all the above and :-

operated the hazards
the curtsey lights
the horn

Can the dual connector 5AS be programmed for the FOB's and ECU I currently have?

Do I understand that you have the Technozen knowledge to perform the required re-programming?

I think I would like to install what I have and make the donor bits work for now but install any wiring necessary to enable the additional functionality for later.

You can end up doing so many mods on the build you can loose track of the project you are trying to achieve if you are not careful.

I may be able to source a 2002 5AS I will likely do that ready, the matching FOB's are possibly lost and the ECU would be for the wrong engine so all I will get is the dual connector 5AS if I can if it can be matched to my VVC ECU!

Lots of questions I am sorry but I love to learn.


JohnC

[technozen]

The earlier 5AS (single connector) doesn't have the ability to flash the indicators or control the courtesy light.

It is possible to have it do these functions, I designed two circuits and posted them on mg-rover.org.

The later version also has a "friendly mobilisation" feature wereby a transponder coil fitted around the ignition barrel excites the fob, this in turn transmits and saves you the bother of having to press the unlock key to start the engine.

The two versions of the 5AS are electrically interchangeable, MG-R supplied the two connector version as a replacement for the single.

You would need to fit the drivers door solenoid as it contains the sill up/down switches which are needed to inform the 5AS that the car is locked.
An aftermarket plunger type solenoid can be fitted as long as it has the built in changeover switch.
The other door motors are simply connected in parallel and are not needed.
The other inputs (doors/boot/bonnet) can be grounded or left open circuit as need be.

The horn on both versions is controlled via the horn relay contained within the MFU.

Everything is programmable!

I have a Omitec T4 handheld unit and the Avon Diagnostics equipment (we have 5 Rover cars in the family!) which cover all eventualities!

Keyfob programming is a doddle and takes about 45 seconds.

5AS matching is relatively straightforward, you can either clone the security number from the existing unit and then program this into the new unit or force the MEMS ecu to learn the code from the new unit.

Ask all the questions you need.