Giant Intrigue X E+ 2 Pro

[Abc123]

Hey I’ve got a Intrigue X E+ 2 Pro put a speed cut thing on it then one day stopped working had the whole bike in pieces worked out it was the controller replaced that and got it going. While I was assembling it I crushed the plug for the speed sensor and ddnt see what wire goes where the motor has red green and blue the sensor has red green and black with multimeter worked out green is earth blue is +5v I’m guessing red is signal dose anyone know what wire goes where on the sensor please

 

[Greg Watts]

Hey I’ve got a Intrigue X E+ 2 Pro put a speed cut thing on it then one day stopped working had the whole bike in pieces worked out it was the controller replaced that and got it going. While I was assembling it I crushed the plug for the speed sensor and ddnt see what wire goes where the motor has ...

@Abc123 Right, so you've got the Giant SyncDrive motor side with red, green, and blue, and the speed sensor side with red, green, and black. You've already done the sensible thing with a multimeter, which puts you ahead of most people who'd just start guessing and frying things.

On the Giant SyncDrive systems, the speed sensor is a simple hall effect type with three wires: power, ground, and signal. Based on what you've measured, if green is ground (earth) and blue is +5V on the motor side, then the remaining red on the motor side is your signal line.

On the sensor side with red, green, and black: green should match to green (ground), which you've confirmed. That leaves you needing to work out which of red or black on the sensor is +5V power and which is signal. Typically on these sensors, black is ground and red is +5V, but since your green is already confirmed as ground, the convention gets a bit muddled with this connector. I'd suggest using your multimeter to check continuity on the sensor itself: the +5V supply pin on the sensor should show no continuity to ground, while the signal wire will typically show high impedance to both power and ground when the sensor isn't triggered.

So the likely mapping is:

Motor Side	Function	Sensor Side
Green	Ground	Green
Blue	+5V Supply	Red
Red	Signal	Black

That said, I'd strongly recommend verifying before you commit to soldering or crimping. With the sensor disconnected, put your multimeter across the sensor's red and green wires and check for a low resistance path (which would confirm red is power, not signal). The signal line on a hall sensor will behave differently, it won't show a simple resistance to ground.

One other thing worth mentioning: the speed sensor on these Giant systems is a known weak point. Community members have traced cutting out issues and error codes specifically to the sensor or its connector failing. The part number for the replacement sensor cable is SR SD071.02 if you need a fresh plug to crimp onto. Alternatively, a reed switch off AliExpress for a couple of quid works as a budget replacement if you just need the bike running again.

 

[Abc123]

@Abc123 Right, so you've got the Giant SyncDrive motor side with red, green, and blue, and the speed sensor side with red, green, and black. You've already done the sensible thing with a multimeter, which puts you ahead of most people who'd just start guessing and frying things.

On the Giant SyncDrive systems, the speed sensor is a simple hall effect type with three wires: power, ground, and signal. Based on what you've measured, if green is ground (earth) and blue is +5V on the motor side, then the remaining red on the motor side is your signal line.

On the sensor side with red, green, and black: green should match to green (ground), which you've confirmed. That leaves you needing to work out which of red or black on the sensor is +5V power and which is signal. Typically on these sensors, black is ground and red is +5V, but since your green is already confirmed as ground, the convention gets a bit muddled with this connector. I'd suggest using your multimeter to check continuity on the sensor itself: the +5V supply pin on the sensor should show no continuity to ground, while the signal wire will typically show high impedance to both power and ground when the sensor isn't triggered.

So the likely mapping is:

Motor Side	Function	Sensor Side
Green	Ground	Green
Blue	+5V Supply	Red
Red	Signal	Black

That said, I'd strongly recommend verifying before you commit to soldering or crimping. With the sensor disconnected, put your multimeter across the sensor's red and green wires and check for a low resistance path (which would confirm red is power, not signal). The signal line on a hall sensor will behave differently, it won't show a simple resistance to ground.

One other thing worth mentioning: the speed sensor on these Giant systems is a known weak point. Community members have traced cutting out issues and error codes specifically to the sensor or its connector failing. The part number for the replacement sensor cable is SR SD071.02 if you need a fresh plug to crimp onto. Alternatively, a reed switch off AliExpress for a couple of quid works as a budget replacement if you just need the bike running again.

Sorry yes forgot to mention red and black wire on sensor with continuity on multimeter makes it buzz with a magnet

 

[Greg Watts]

Sorry yes forgot to mention red and black wire on sensor with continuity on multimeter makes it buzz with a magnet

@Abc123 That's a useful bit of detective work. If putting a magnet near the sensor causes continuity between the red and black wires, that confirms red and black are your signal and ground pair on the sensor side. A hall effect sensor pulls its signal line low (to ground) when a magnet passes, which is exactly what you're seeing.

Since you've already confirmed green is ground on both sides, the mapping should be:

Motor Side	Function	Sensor Side
Green	Ground	Green
Blue	+5V Supply	Red
Red	Signal	Black

The logic being: black on the sensor is the signal output (it's the wire that changes state with the magnet, shorting to ground when triggered), and red on the sensor is the +5V power feed. Your multimeter test basically proved the signal wire's behaviour for you, the sensor is an open collector type that connects signal to ground when the magnet is present.

Before you crimp or solder it all together, I'd suggest a quick bench test. Connect it up loosely, power the bike on, and wave a magnet past the sensor to confirm you get a speed reading on the display. Saves you having to tear it apart again if something's off. And while you're at it, check the gap between the sensor and the disc magnet is in the 5-17mm range, as @calvintys noted the stock magnet can have gap issues that cause intermittent errors down the line.

 

[Abc123]

Sorry yes forgot to mention red and black wire on sensor with continuity on multimeter makes it buzz with a magnet

But what has me wondering on all the other loom each wire has the same color on the other plug why should they change that on only the speed sensor