CB Custom - Speedo/Tach Wiring Issues

[Lord Popgun]

You understand I hope, that the serial data line is a bi-directional data line. Digital information. We, on the board, do not know the data format. The info transferred is in the service manual.

I have done some research on the speed sensor. Using a scope I got nothing unless i put the probe on one wire and the probe ground on the other wire. Grounding to the chassis didn't work. Needed a signal ground, I guess.

[Cormanus]

CafeBandit, I’ve deleted your attachments I’m afraid. We do not allow reproduction of copyright materials on the forum.

[pekingduck]

You understand I hope, that the serial data line is a bi-directional data line. Digital information. We, on the board, do not know the data format. The info transferred is in the service manual.

I have done some research on the speed sensor. Using a scope I got nothing unless i put the probe on one wire and the probe ground on the other wire. Grounding to the chassis didn't work. Needed a signal ground, I guess.

LP, when I was testing CB1100 speed sensors for my cast/wire wheel swap, I was also unable to get any voltage signal off any kind. That was despite using 4 different analog and digital meters, and a test harness that let me test every possible way.
I was able to pick up a signal on a milliamp scale though. I scratched my head and gave up at that point.

My understanding is that the serial data line is for fuel mileage calculations for the display only, but it looks like it also is for the FI light. Does that sound right?

Thank you all. Yeah, its a brand new gauge from Daytona. They themselves dont even have a lot of info for me, too soon for google also. Im just winging it at this point. I know its risky but it will be worth it in the end. Thanks to the plandemic I have nothing but time.

I currently still have the original gauges connected and stored under the seat so hopefully it will run as designed but with the digital aesthetics if i could just tap in. The install manual showed that if the rpm and speed pulse were connected to the ecm , it would give me the gear indication. But i just cant figure out the ecm wires. The ones i followed from the rear speed sensor (pink/white) (green/red) are not giving me anythingm ive tried many variations to get a reading but nothing.

Ive read before about the serial data bus but again I cant figure out which wire, to test it out. The tacho is labled clearly but again nothing happens when I tap in. I grounded the new gauge, connected positive to batt. Dont know if that matters or not but cant think of what else could keep it from reading. I got the power, nuetral, gas, turn signals so far, not concerned with the temps or warnings because of the stock gauges.

I guess I will have to used the after market speed sensor, and rpm reader on the coil but that leaves me with no gear indicator, unless of course I install a seperate one. Kinda defeats the all in one digital but thats worse case.

[/quote]
Looks like you're making good progress. I have found that the wire around the spark plug cable has been most reliable, but don't know if it can be calibrated to compensate for a "waste" spark, or will it just read 2 X the rpm.

When you use the magnetic pickup, I recommend using it on the rear wheel so the wiring and sensor are less visible. You could mount it on the sprocket.

As far as the gear position indicator, it looks like it is a calculation that the new meter learns from comparing road speed to engine RPMs. Once you have the tach and speedo functioning, just follow the instructions. You can send me or others on this thread a PM with your shop manual excerpts.

[Lord Popgun]

PD, going from memory the OEM gear position is just a multi position switch that puts a ground on different lines that will then cause the proper gear position to light. It is effectively a code, but there ya go.

If the new on works like you say, it works pretty much like the GiPro I have.

I will have to look at the manual to see what data goes back and forth on the serial data line. I *think* it is in chapter 5.

As far as the speed sensor IIRC I made a video of the pulse train and put it on youtube. Yep, Here is the link: https://youtu.be/JLJi-v2Ju5A

Here is the thread: http://cb1100forum.com/forum/showthread....eed+sensor

[pekingduck]

PD, going from memory the OEM gear position is just a multi position switch that puts a ground on different lines that will then cause the proper gear position to light. It is effectively a code, but there ya go.

If the new on works like you say, it works pretty much like the GiPro I have.

I will have to look at the manual to see what data goes back and forth on the serial data line. I *think* it is in chapter 5.

As far as the speed sensor IIRC I made a video of the pulse train and put it on youtube. Yep, Here is the link: https://youtu.be/JLJi-v2Ju5A

Here is the thread: http://cb1100forum.com/forum/showthread....eed+sensor

Popgun, yes correct that in all years US CB1100 models use a rotary multi-position switch for gear indicator. 2013 models did not use serial communication line, but had a white/blue wire to ECU marked Warning that likely is for FI light.

Looks like the 2-wire GIPro gear indicator has the same logic as the Daytona to "learn" the parameters for reading rpm curves and speed curves and determining which gear it's in.

And I did see your video on the speed sensor on the scope, perfect 5v DC square wave. Did you use a 2013 speed sensor? And were you able to get any results on a multimeter?

I was using 2014 and 2017 sensors, getting no reaction from any multimeter except milliamps on one. Honda used to recommend a simple "screwdriver" test in their shop manuals, but has been missing for a while.

[Lord Popgun]

PD, yes on the 2013 speed sensor as my bike is a 2013. Never tried a meter as I knew it would be a pulsed signal that varies with speed.

And as you mentioned, I do know the ‘10-‘13 models do not have a serial data line.

[max]

Guys this may be helpful to explain how these sensors can be tested and how they work;
https://www.tiepie-automotive.com/en/art...ensor-hall

It seems an adaptation of the 4-20 mA system, you supply a dc voltage through a resistor from the controller end to a two wire hall effect sensor, the sensor changes the current in the two wires by switching in a load ( in parallel ) with each " post " that travels past it's surface which changes the current through the sensor.
The sensor uses 5 volt logic and thus needs just over 5 volts to operate, the rest of the 12 volts now acts to convey the speed sensor data pulses ( frequency or speed ) to the controller
This also changes the voltage measured across the sensor leads which is exactly what PG's scope shows.
Apparently the controller recognizes this signal and translates this in abs and/or speed sensor lingo.

So any multi meter should be able to measure the " gaps" when connected across the sensor connector and as long as they are presented very slowly so the meter can react to the varying voltage on the two sensor wires, you would expect the meter to indicate something like 6 volt dc on a post and 6.5 volt dc on a gap, ( for example ) so read the meter carefully, as long as there is a clear and repeatable variation in voltage.

Have not actually done this on my bike but with PG's video this seems correct, the trick is to understand how the pulses are being generated and delivered to the controller.

[pekingduck]

Thanks Max for that link. Our bikes use a 2-wire sensor. When I was looking into my particular speed sensor problem, I also found inductive sensors and reed switch sensors (Trail Tech uses reed-switch type) and one other distinct type I've forgotten. And all of them look the same or similar externally, and none had any markings.

I remember back about 15 years ago when Honda started using speed sensors on their bikes and ATVs, you could hook up an analog meter and it would register a 5v square wave when the wheel was turned slowly, didn't matter if ACV or DCV. I'm getting nothing on the new sensors. I need to find an older sensor to test.

[Lord Popgun]

I would use an analog meter (D’Arsonval movement) as a digital meter typically won’t respond fast enough.

[GoldOxide_imp]

Many current/new (and some wireless) low-cost "DVM"s now display signals up to a few MHz that is in addition to the usual functions. Some even capture the signal waveform and store it on your mobile device.