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Frequently Asked Questions - Wiring & Sensors
 
Use of gear change light wire for rad fan control
Reasons for Clutch & Launch switches
Neutral Button functions on Gearchange system
Crank sensor/trigger wheel positioning after an engine re-build
Crank sensor problems
Changing from standard Hayabusa wiring to a SBD wiring harness
Throttle position sensor types
Sensors for Cosworth engine
 
Crank sensor problems
Question: I have a problem with the crank sensor it showed bad crank tooth pattern and wiring error. Initially I thought it might be due to the fact that I did not use the trigger wheel supplied by you but one that was supplied by QED (one piece with front pulley). I have replaced it with the one supplied by you with the Ford crossflow kit. Still shows bad crank tooth pattern as well as wiring error. Crank sensor is the one supplied with the Ford cross flow kit (Magneti Marelli). Loom is the standard rear wheel drive. Extension to link it up to the crank sensor was supplied by you.
I had to make up a bracket for the crank sensor because the twin cam front cover is quite different from the ford crossflow, but I went into pains to get the position and gap right so I think there should be no problem there. I haven´t started measuring through the wiring yet because frankly I did not know what to look for yesterday. I would be grateful for some tips.

Answer:The warning you are getting is to help point you in the right direction, it is impossible to get the software to diagnose the exact fault, it simply means that it is struggling to read crank teeth correctly in order to start the engine. It could be any number of things but I have listed them in order of which they should be checked:

1. If battery voltage is too low during cranking, the time between each tooth may be inaccurate due to speeding and slowing down of the engine. To eradicate this possible cause, get a separate battery and connect the positive and negative terminals of our wiring harness to it, place the switched ignition wire directly to the positive post when attempting to start, make sure there is no connection with any other part of the car, connect the fuel pump directly to the car's battery and not our system during this test. This means that the ECU, injectors and coils are the only drain on this battery, then when you attempt to start the car, the car's battery has no connection and cannot cause voltage drop. Even if this does not fix the problem, I suggest you leave it wired in this way until the problem is fixed, make sure you maintain the batteries in a full charged state otherwise you may find that you have actually fixed the problem but due to low battery voltage, the engine will not start and you will assume you haven't fixed the problem. This is particularly important when you are starting a new engine for the first time on fuel injection.

2. Due to the fact that your engine is new to fuel injection, the fuelling may be out by a factor, this makes it much harder for the engine to start because of the possibility of the incorrect amount of fuel being available during starting and this cannot be accurately determined until the engine is running (catch 22). The software itself shows the potential for an error in crank trigger wiring because it's unable to calculate the tooth pattern to it's satisfaction, therefore it will not fire a spark until it is happy to do so. If the engine is slowing down in this period and speeding up due to compression or other issues, this could take it outside its operating window for safely starting. Remove the sparks plugs and see if this fixes the crank trigger warning, obviously once the plugs have been removed the engine will turn over easier and give a more consistent speed allowing the ECU to calculate the tooth pattern more accurately. Because the warning you see on Easimap needs to say on the screen long enough for you to read it, there may have been a time during cranking that the ECU was able to calculate the tooth pattern correctly but due to the fact that the fuel was totally incorrect, the engine was unable to start and the engine slowed down due to poor battery voltage and therefore wouldn't start because of 2 separate problems.

3. Crank sensor wiring, normally if you are using a 36-1 trigger wheel, the crank signal is on pin 1 of the crank sensor, if your trigger wheel was 60-2, the signal would be on pin 2 of the crank sensor (this is MBE specific). You may not actually know which is pin 1 and which is pin 2, but the easiest way to test it is to simply swap the 2 wires around and carry out the test twice. This is easiest to change in the ECU connector hood taking only seconds. See the link to the hood information and the crank sensor wiring. Since you are running 36-1, just confirm by looking inside the software in basic engine set up that the trigger wheel is configured for this, provided when you ordered the kit you confirmed that you were running 36-1, the ECU will be configured correctly.

4. Crank sensor position, ensure the sensor is mounted correctly. The sensor that you are using in combination with the trigger wheel should run directly over the centre of the tooth with a 0.5mm to 1mm gap.

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Use of gear change light wire for rad fan control
Question: Are you able to confirm that I could use the spare wire (i.e. gear change light) to connect to a relay to allow the cooling fan to" run on" after the engine has been switched off?

Answer: Yes, you can use the gear shift light output for rad fan control. You would simply use the switched negative as the negative side of a normal 30amp relay and use the output of the relay to power your fan. The instructions that show you how to wire a shift light using a relay are identical to that required for using your rad fan. You would simply then need to configure the output to come on at say, 750rpm and on at 85 degrees and off at 80 degrees.

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Reasons for Clutch & Launch switches
Question: What are the reasons for Clutch & Launch switches?

Answer: Clutch Switch is for sensing pressure on the Clutch pedal. This effectively allows the ECU to sense that the driver has rested his foot on the clutch and potentially disengaging the clutch mechanism. This allows the ECU to do two things, prevents the gearbox doing down shifts and damaging the engine, e.g. if the car was in top gear the driver rests his foot on the clutch, the engine is disengaged from the clutch and the rpm drops. The driver could effectively then downshift from top to 1st gear, let the clutch up and obviously destroy the engine.

The second use for this switch is that when the driver is in the car, the system senses that the clutch is being pressed and therefore allows the paddles to select a gear safely.

If at least one wheel speed sensor is fitted, a minimum speed can be programmed into the ECU so that the engine can go down the gearbox. This is normally programmed to the maximum rpm below the rev limiter in first gear e.g. if 1st gear was 60mph at 10,000rpm, then unless the wheel speeds were below 60mph then the clutch was pressed, then no gear changes will happen until below that speed.

If a clutch switch is not fitted, then the driver would need to press the neutral button to tell the ECU that he is ready to select a gear, he then pulls an up or down paddle whilst holding the neutral button. The ECU will then select a gear.

The Launch switch is used to control Launch and provided the Launch circuit is fitted and set up, this can be used in a similar way, but you must remember that Launch is designed to operate when the clutch is on the floor and therefore if the driver simply rests his foot on the clutch pedal then he can actually have the clutch disengaged but not have triggered the switch and therefore downshifts could still occur and damage the engine.

So my suggestion is normally Clutch switch is most important for safety and should always be considered the first option and the Launch switch is for Launch and only used as a back up.

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Neutral Button functions on Gearchange system
Question: What are the Neutral Button functions on Gearchange system?

Answer: You must fit a Neutral Button, otherwise the ECU will not know when you want Neutral. The Neutral Button does two basic jobs :-

1. Select Neutral.
2. Selecting a gear if no 'Clutch Switch' is fitted. The driver presses Neutral Button, then pulls a paddle. This stops the driver or any one else accidently pulling a paddle and selecting a gear if the engine is running.

Fitting a 'Clutch Switch' means the ECU knows when the clutch is down (I use a brake light pressure switch Banjo Bolt quick and easy to fit). You will then be able do the following.

1. Select a Gear without  pressing the Neutral button first.
2. Start the Engine when in Gear.

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Crank sensor/trigger wheel positioning after an engine re-build
Question: In your opinion and with knowledge of the ECU and how it works, I wonder how critical it is to get the crank sensor/trigger in exactly the right spot.

Answer: The trigger wheel positioning is extremely important on all engines and if it is not positioned in exactly the same place as it was when the engine was mapped, at the very least there could be a drop in performance and at worst engine damage or failure could occur due to the timing being out.  So unless you are 100% confident that it is correctly positioned, I would suggest your only option is to have it re-checked.

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Changing from standard Hayabusa wiring to a SBD wiring harness

Question: I have a 1999 std Busa engine that I've mounted in a custom made Ali. Box chassis. I'm building a one off fast road car as a bit of a toy. And I'm stuck! I plan to keep the motor stock as its fast enough for what I want. I've looked at your web site and think you have what I need to get it running?

I have all the original loom and ancillaries but it looks way too complicated and over the top? I would like you if possible to tell me what I need. I need a simple loom, I assume a new ECU? In time I want to have a power shift on it but that’s another budget. Can you supply costs for this?

My idea is to have a paddle shift off the steering wheel. Do your looms just plug in?  What electrics do I need to save from the old loom? I assume I need a charging circuit and a ignition circuit? I'm not too worried about lights etc as these can easily be done on a separate switched circuit. Also do I need to alter the charging rotor thing? If so is there an exchange option for this part? How does the old one come off?

So in summery could you please list out what parts I need to buy from you with prices and supply some simple instructions to enable me to do it!! Have you a full typical circuit diagram showing what parts of the existing loom/wiring I need to save? The engine does run but I know it can be much simpler. In your loom do you cut out most of the silly sensors? Does the std fuel pump (mine is on the back of the engine) plug straight in? is it a simple plug in start up and go system? I don’t want to make an expensive mistake here.

Answer: Fortunately you have detailed everything you have and everything you require.  The installation of our system will be extremely simple by comparison with what you have there.  Most of our harness will simply plug in to the original coils and sensors and what sensor you don't require will simply be eliminated.  The only update we have carried out recently to our wiring harness is to change the injector connectors to make them more user friendly for future engine updates, but it is a fairly simple process to either add or make simple adaptors to convert from the standard Suzuki injectors to our wiring harness (there is no cutting of our wiring harness).  If you are ok with a heat gun and a crimp tool, it is no more than 1/2 hours work.  There are instructions within the installation instructions of the kit that show you in pictures how to modify the connectors, which you would remove your existing harness.  The connector kit is included in the price.  If you feel this is something you would not like to tackle for yourself, simply send us your sub harness and we will charge you 1/2 hour to carry out this work for you.

The charging circuit is relatively easy to modify but we do make a simple charging harness, which is made for one of our American customer which simply plugs into the generator and the regulator pack and then gives you 2 wires for positive and negative.  I have also included this in the quote.

The small modifications you require to carry out our simple wiring, again if you feel that this is not an area that you are comfortable with, these components could be sent to us and we could modify them for you at the same time.

Your original fuel pump can be used, the only issue you could potentially have is that on the motorbike the petrol tank is mounted about the engine and therefore the fuel is gravity fed to it, when fitting it to a car you would need to ensure that the pump is mounted lower or at least at the same level as the bottom of the fuel tank, so you may need to reposition it.  Alternatively, if your budget allows, you could a more traditional supply and return system and replace the fuel pump, fuel rail and fuel regulator to suit.  I  have not quoted you for this at this moment in time as you will better for yourself as to the installation of your car and what is and is not possible.

The generator trigger wheel is easily changed with the correct Suzuki tool or if you are suitable mechanically minded, it wouldn't be too difficult to produce something for yourself.  Effectively you need to remove the generator cover, then there is a bolt retaining the generator rotor which locks it on to a taper and key.  You simply undo the bolt, which exposes an external thread, the Suzuki tool is then tightened into this thread, there is then 2 flats on either side of the generator, which can be held with a spanner.  This then pulls the generator off the crank, the generator itself on the early engines such as you have, has 8 teeth and you require a 24-1 which is fitted to the 2003 - 2007 engines.  Although in the past some people have tried modifying the original motor, because metal has to be add in to some of the gaps, they usually damage the magnets of the rotor itself, so we do not recommend this option.  It is best to hunt through Ebay or similar to look for a second hand unit, new units are available but are very expensive. 

Once the system is fitted and the throttle position sensor is adjusted, which can be done with a volt meter, with the standard map loaded which we would supply in the kit, your engine will be ready to run and use.  I have also attached the link for the fitting instructions, which gives you pictorial information to show how easy it is. 

LM9A4-GSXR-M-OMS-2 fitting instructions

It may be worth a phone call to speak to me directly as quite often questions you may have, that you may feel are complicated can be simply answered on the phone.  The system you are looking at is, we believe, the simplest on the market and we supply this kit worldwide to trade and retail alike.  If you wish to upgrade your engine and other components associated with it, it can be easily done.  You mentioned about Powershift, the standard wiring harness that we supply has a Powershift connector built in and the ECU will be programmed and ready to use it as standard.  You can simply then order the Powershift unit, which you fix to the lever on the gearbox and connect the other end of the cable to your steering wheel paddle or gear lever.

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Throttle position sensor types
Question: I was wondering if you would have a throttle position sensor connector that I could change on the loom to suit the connector on the actual throttle position sensor?

Answer: The connector shown in your photograph is a hard plastic connector fitted to your throttle position, which in my opinion a low grade connector. It is very rigid and this imposes a high stress point where the connector meets the wiring harness, potentially causing fatigue (the reason this plastic connector is used by a few companies is that it is historical).

We supply 2 types of throttle position sensor; the more basic Culven type (PT1), which we normally cut the connector off before despatch or the contactless PT8 type, this sensor we have made with a 3-way sureseal to match. We would always advise not to modify a professionally made harness if at all possible. If you change the connector on the throttle position sensor itself, then only the sensor itself needs to be replaced if any faults or failures occur as opposed to potential harness faults, which normally incur greater issues which are sometimes harder to find and fix.

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Sensors for Cosworth engine
Question: I am going to use a MBE 941 Ecu on a Ford Escort Cosworth. It would be great if you could tell me what for sensors i need? And do you sell any coils so i can run distributor less ignition?

Answer: The 941 ECU has been discontinued. You will need to use the current MBE9A4. You would need to fit a 60-2 or 36-1 trigger wheel to your Cosworth engine. You can usually use the original Cosworth sensor or we can supply a special one (CRK-SEN5), boost pressure sensor, air temp sensor and a distributorless coil pack (COIL-4). We would normally recommend replacing the water temp sensor, we would use a Bosch version. This keeps things simpler than trying to match your Ford sensor. We would also recommend you use high ohmage injectors i.e. 12 - 14.

Links: MBE9A4 ECU | Crank Sensor | Boost Pressure Sensor | Air temp sensor | Coil pack

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Please check our customer cars section which may help answer your questions
 
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