Most Tesla iBoosters you can buy on eBay or elsewhere come without connectors. If you are lucky they do come with connectors and a bit of wiring. In that case you will still need to extend wires and attach them to your wiring loom. And where to connect which wire to what anyway? This article explains the ins and outs of wiring the Tesla iBooster into your car.
It becomes quite straightforward using the GEN1 connector kit and the GEN2 connector kit available from EVcreate with all connectors, terminals / crimp pins, seals and blind plugs. Moreover you will be able to fully integrate the iBooster into your wiring loom.
Stand alone mode: no CAN-BUS needed
The iBooster ECU has two CAN-BUS connections which are connected to the vehicle CAN and the Yaw sensor. Here these two are not used and instead of crimp pins, blind plugs are provided in the connector kits. Instead we rely on the ‘failsafe mode’ of the iBooster. In that mode the iBooster just uses the input from the travel pedal sensor (integrated onto the iBooster) to operate. Furthermore it requires 12V+ and GND inputs. Below it will be explained in more detail. It is possible to control the iBooster over CAN, we’ll dive into that in the future. Any input or experience on that is welcome.
To a large extent the wiring of the GEN1 and GEN2 is identical. Main difference is that the GEN2 no longer uses pin 17 for permanent 12V+ to the ECU and above all the travel sensor connector and it’s pin numbering is different. The travel sensor itself is part of the iBooster assembly, see below photo’s. It just is not internally connected so you need to wire it.
Below you will find detailed wiring and pinout instructions for both.
GEN1 iBooster wiring
Electronic Control Unit (ECU)
- 1 = 12V+ permanent 40A fused
- 2 = Pedal sensor 1
- 8 = Pedal sensor 3
- 9 = GND
- 17 = 12V+ permanent 5A fused
- 20 = 12V+ ignition 5A fused
- 22 = Pedal sensor 2
- 23 = Pedal sensor 4
- to ECU 2
- to ECU 22
- to ECU 8
- to ECU 23
Recommended wire sizes
Firstly de main power pins (1 and 9) which are the largest terminals (4.8 spade) and are intended for 2,5 – 4 mm² wire (Tesla uses 4 mm2) and the seal included in the kit accepts an outer diameter of Ø3.4 – Ø3.7 mm. Secondly pin 17 (the additional 12V+ permanent) which is the medium terminal (2.8 spade) and is for 1,5 – 2,5 mm² wire and the seal is for Ø2.0 – Ø2.7 mm. Finally the small terminals (1.5 spade) for the 12V from the ignition and the pedal travel sensor accept 0.35 – 0.5 mm² wire and Ø1.6 – Ø1.9 for the seal. Unused entries can be closed off with the appropriate blind plugs.
GEN2 iBooster wiring
- 1 = 12V+ permanent 40A fused
- 2 = Pedal sensor 2
- 8 = Pedal sensor 4
- 9 = GND
- 20 = 12V+ ignition 5A fused
- 22 = Pedal sensor 1
- 23 = Pedal sensor 3
- ECU 22
- ECU 2
- ECU 23
- ECU 8
Firstly identical to the GEN1, pin 1 and 9 are the large terminals (4.8 spade) and are intended for 2,5 – 4 mm² wire (Tesla uses 4 mm2) and the seal included in the kit accepts an outer diameter of Ø3.4 – Ø3.7 mm. The GEN2 iBooster does not use pin 17 (medium size terminal). Secondly the small terminals (1.5 spade) for the 12V from the ignition and the pedal travel sensor accept 0.35 – 0.5 mm² wire and Ø1.6 – Ø1.9 for the seal. Finally again, for unused entries the connector kit contains appropriate blind plugs.
iBooster power draw
Tesla uses a 40A fuse for the main power input and 5A for the ignition and in case of the GEN1 the secondary 12V permanent. For the GEN1 after switching the ignition off the current shortly still is 250 mA and then drops to 1,2 mA.
Blog series on power brakes
- Vacuum assisted power brakes
- Electric power brakes
- Installing the iBooster
- Wiring the Tesla iBooster
- Performance test of the Tesla iBooster
- CAN control of the iBooster
Disclaimer/warning that is not only valid for this article but applies in general.
It is the sole responsibility of the person or company selecting or installing any component or kit in any car modification or upgrade (like brakes, drivetrain, etcetera) to determine the suitability of the component or kit for that particular application. Especially when using parts or components that were not directly designed for use in that specific brand or model. If you are not sure how to safely use a part, component or kit, you should not install or use it. Do not assume anything. Inspiration and information found on this website, elsewhere or examples that others are using a part, component or kit does not guarantee proper installation or match with your particular setup.
16 thoughts on “Wiring the Tesla iBooster”
Id like to know what kind of travel pedal sensor you areq using and part number if you have it. By the way really good blog
Thanks! The pedal travel sensor is part of the iBooster. I have updated the blogpost and added photo’s for clarification. This question was asked a lot so apparently not explained well enough so far.
We swapped the gen 2 iBooster into our vehicle .
We are experiencing the brake pedal to continue to build boost and not release. We will of course dig in and check calipers and lines… but they worked fine before the swap. I wanted to know if you had any thoughts about the issue. This link has mentioned the same issue we are having (https://car.inotgo.com/2021/10/20211011041849532k.html)
Our gen 2 ibooster is from a 2018 honda accord.
Wel, I’ve had the same situation/issue with a GEN1 iBooster.
I my case it was a misaligned (out of range ?) travel sensor.
Unfortunately I have not been able to reproduce the issue to further investigate it, but I think this was caused by either the zero position of the pushrod not being within the measurement range of the internal sensor or max pedal travel outside the range of that sensor.
In my case this was resolved by moving the sensor a bit, but this is not possible for the Gen2 and also not recommended.
I’d check push rod positions. Hope this helps, please let me (and others) know by replying here if you manage to solve it.
Thanks for an awesome manual!
There’s one thing I wonder though and that is if you can get brake light output and/or brake signal (0-5V) from the iBooster Gen 2?
I have started to mess around with it and it seems to work fine so I’m only needing some outputs.
Well, there is no analog or digital output specifically for this. I would not interfere with / tap into the pedal travel signals so that leaves CAN-BUS as the remaining option. I have not checked it for Gen2 but I think that is similar to Gen1 so I expect push rod travel is a parameter on the bus. So you can use that to enable a brake light.
Check out my iBooster CAN-BUS research blogpost for further information.
on the bench it works occasionally, if I keep the rod pressed while I give tension, it starts, but it goes without the wire locked, and then it stops after a while. Maybe I have to install it and so does the pedal calibration because I read above that the 0 position is not good. I leave you the link of the 2 videos. the first when it works and the second when it stops working.https://photos.app.goo.gl/GBUh3qe4v3BztYF49
I did other tests, it works if I connect pin 20 for a moment and immediately disconnect it. so it works, if I connect the pin 20, it stops working and then it moves a bit. you can see it in the video. maybe once mounted in the car and done the calibration, then it’s fine, I hope.
Now I’m wondering if I’ve made the right connections. https://photos.app.goo.gl/YhjGe7eopAcFnnKh8
Are the pedal sensors integrated into the unit or do they accurately need to be mounted to the pedal?
See paragraph 4 of this article:
I put the iBooster renault captur into operation, it was sufficient to connect it to the can bus, and it started to work like the ones you tested, if the car does not have the can bus, then just connect the two can outputs of the ibooster with a resistance of 60 ohm. or 2 of 120. Then I configured torque, orion bms, and I see on torque how many mm the brake is pressed….cool.
Thanks to your site I was able to do it.
Thanks, glad to hear it worked and thanks for sharing! So you have a .dbc for the Renault Captur iBooster to read the pedal travel? Then I can add that to my CAN control info post.
Thanks for these blog posts. I finished installing the ibooster into my EV conversion a few weeks ago. Today I finally took it on an extended drive and came across an interesting issue. At some point, on the freeway, I noticed my brakes were stuck on. As in the booster was applying brakes when I was not. It didn’t release until I disconnected power from the ibooster. Reconnecting the ibooster in fail-safe mode, it resumed working as usual. Have you heard of this before? I only experienced it once so far and so I’m still observing if it occurs again but it caught me by surprise today.
Well, actually I had the exact same issue. Think this is caused by travel sensor position at IDLE and calibration of the iBooster travel sensor when you power the iBooster up. I solved it by slightly moving the travel sensor but this is not the best solution. But in our case we were on our way to the ferry and there was no other option.
Think the structural solution is to adjust the push rod length.
I could adjust the push rod going from the pedal into the ibooster. Which direction did you adjust the sensor?
Don’t remember in which direction I adjusted the sensor, but I would not recommend that. Adjusting your push rod seems the way forward to me.