Forgive my absence if this has been discussed previously.

Forgive my not searching for it on this site.

Can I just wire the fuel pump relay ON while the kill switch is ON and wire the solenoid to the START button to bypass the immobilizer on an ‘07 S4Rs?

Stupid bike left me stranded today.  It’s a salvage title bike with 25K miles so I don’t plan on investing mucho bucks to fix this...

I don't know for sure Stu, but your idea should work assuming the immobilizer doesn't also mess with ignition.

Yes and my other concern is whether or not the ecu turns off the 5V to the injectors and TPS.

I've wired directly from the start button to the solenoid on a couple Immo bikes that torched that particular circuit in the ECU.
But that was only to bypass that part.

I'm thinking the Immo cuts off the opening of the injectors for sure.
It may well just interrupt the signal from the trigger, I've had bad triggers and the ECU only adds fuel if it thinks the motor's turning.

Like most anti-theft devices it's a total PITA when it malfunctions.
Not sure how high they set the bar on defeating it, largely a 'make it more difficult than that other bike over there' deal I think.
Dunno, with the 4 guys, a mattress and a van routine maybe delay is immaterial.

Salvage titles S4Rs, so putting big $ into it is not an option (that’s the reason for this whole thread.)

So, I’m going to check the presence of 5V @ the TPS.
I’m going to check the presence of 12V feeding the ignition/injector relay.
I’m going to check whether or not that relay pulls in when the kill switch is ON.


Will post up with any progress.  May be a while. Riding isn’t a big priority for me these days.

Forgive my complete ignorance, most hallowed gentleman. Isn't it simpler to reflash the ECU and do away with the immobilizer altogether? Or is that an example of more expensive?

I ask because Ducvet reflashed my ECU a few years ago to get rid of some of the S2R1000/lambda sensor/lack of lambda sensor/low idle issues a few years ago, and while he was in there..... No more immobilizer.

I assume that it's not as simple as that?

I'm not certain, but...I'm thinking Stu doesn't want to spend a couple of hundy on this bike.

Quote from: ducpainter on September 18, 2020, 02:11:57 PM
I'm not certain, but...I'm thinking Stu doesn't want to spend a couple of hundy on this bike.

I’m at a financial tipping point on this bike.  I couldn’t care less about the fact that it’s an S4Rs.  It’s a salvage titled “get us through the next couple years” vehicle.  So, I have time and always wanted to see if this could be done.

So yeah, it’s $.  If I put too much into this, less $ to redo the Bobber...

Some of the xdf files for the 5am ecu have the immobilizer  position marked. I have not tried it to see if it is correct but that would just need a cheap cable & iaw flasher.

Wired to kill switch:
Relay for injector/ignition power (same relay)
Relay for fuel pump

Wired to start button:
Starter solenoid

So far, consensus is that this should work.  I will need to check for the presence of 5VDC at the TPS and the timing sensor though.

Although I share the same logic, I have tried this and not had any success.

I went through the wiring diagram of my S2R1000 in pretty detail and discovered that the injector system is independent of the immobolizer system and tried to isolate it the bike would never turn over. I thought I fried my immobilizer by accident but when I bought a brand new harness and wired it up, it was working just fine. Granted I could be reading the diagram incorrectly (which is a high possibility because there are a few circuits in the diagram that make no sense to me).

As capeirx said, the XDF files for the 5AM ECU are readily available , so you may be able to just shut it off with a $5 cable and a bit of patience.

But did you wire the solenoid to the starter button?

I missed that bit. I did not, but I did jump the relay and cycled the starter by touching the two leads on the starter relay and it would just crank forever, so in essence its the same thing I believe.

If I understand the circuit correctly, the starter relay is directly connected to the battery on one end and the other goes to the starter. The starter relay also has a two wire pig tail. Both those wires connect to the starter button which closes the circuit. In between the starter button and the starter relay is some logic that the computer has to pass in order to engage the starter. That logic might include the injectors.

If the starter is forced to crank but the bike does not start, my only logically reasoning is that the injectors are not firing, which means they are dependent on the immobolizer disengaging. I guess the best way to check this is as you said, check for voltage at the injectors when you crank the starter. The injectors are simple enough. If they get juice, they fire, so if they dont fire, then obviously the ECU is not sending the power to the injectors which means they are in fact tied to the immobolizer which is a huge bummer.

I still think the XDF and bin file is your best bet.

I can't go that route simply because I don't even know what bin file my ECU is running right now!

Battery is charged.  Going to futz with it some tonight.

The LonElec cable is $31 shipped to my door, so that’s likely my fix.  We’ll see if a charged battery helps anything tonight (not that it was low mind you...)

One thing that sprang to mind just now

My OEM ECU one of the spark channels went bad
I swapped everything else around, injectors, coils, swapped leads on injectors and the problem stayed put on the vert
Not significant here other than if you swap injector leads, apparently the injectors are timed and it's definitely not a better tune.
Runs just sounds crappy.
I have not tried that since so maybe I was getting bad data from experimenting with a wounded part but in a swap/debugging fiesta red herrings get thrown around.