Clutch and brake pedal sensor problem!

[Lando217]

Hey guys I don’t know if I wired something wrong or what, but my goblin doesn’t start if the clutch pedal or brake pedal is applied.. it start up great without pressing the pedals. Are my wires backwards or is there another position the sensors can be bolted up? Anyone else have this problem? Thanks! 08 ss/tc

 

[Lonny]

Do your brake lights work?

 

[Lando217]

Do your brake lights work?

I have not wired them up yet, but I will get on that this weekend and let you know! Thanks

 

[ctuinstra]

Hey guys I don’t know if I wired something wrong or what, but my goblin doesn’t start if the clutch pedal or brake pedal is applied.. it start up great without pressing the pedals. Are my wires backwards or is there another position the sensors can be bolted up? Anyone else have this problem? Thanks! 08 ss/tc

Yep! We did. On our car they are the exact same connectors and we had the brake on the clutch and the clutch on the brake. It will start only in the most dangerous position - no brake and no clutch!

Like Lonny said, check the brake lights when you get them wired up or simply try swapping them, it won't hurt anything, they are simply switches.

 

[Lando217]

Yep! We did. On our car they are the exact same connectors and we had the brake on the clutch and the clutch on the brake. It will start only in the most dangerous position - no brake and no clutch!

Like Lonny said, check the brake lights when you get them wired up or simply try swapping them, it won't hurt anything, they are simply switches.

I will try that out, thank you!

 

[Lando217]

Yep! We did. On our car they are the exact same connectors and we had the brake on the clutch and the clutch on the brake. It will start only in the most dangerous position - no brake and no clutch!

Like Lonny said, check the brake lights when you get them wired up or simply try swapping them, it won't hurt anything, they are simply switches.

I have not wired them up yet, but I will get on that this weekend and let you know! Thanks

Wired me tail lights and the brake lights work with the pedal.
I switch the connectors to try that out and the brake lights stop working. I am assuming they were correct the first time. Could the sensors not be working?

 

[Yustas]

Clutch pedal position sensor (as well as brake PPS) is not just On-Off switch. It is a variable resistor. 2 reference voltages and 1 signal line.
ECM (in case of clutch) is trained for specific sensor for specific installation.
I believe both clutch sensor and ECM are from the same donor. If not - it might be the reason and relearn procedure required.
Other issues might be:
1) incorrect soldering: swapped reference voltage lines or added resistance on these lines
2) different placement of the sensor compare to its original installation (which is ECM was learned to). In fully pressed of fully depressed position ECM can get our of range values. Try to release the sensor holding screw, then "rotate" sensor (counter-)clockwise around anchor pin, there is some small play, and screw it in this position.

 

[Lando217]

Clutch pedal position sensor (as well as brake PPS) is not just On-Off switch. It is a variable resistor. 2 reference voltages and 1 signal line.
ECM (in case of clutch) is trained for specific sensor for specific installation.
I believe both clutch sensor and ECM are from the same donor. If not - it might be the reason and relearn procedure required.
Other issues might be:
1) incorrect soldering: swapped reference voltage lines or added resistance on these lines
2) different placement of the sensor compare to its original installation (which is ECM was learned to). In fully pressed of fully depressed position ECM can get our of range values. Try to release the sensor holding screw, then "rotate" sensor (counter-)clockwise around anchor pin, there is some small play, and screw it in this position.

Thank you! I will try these points you recommended and see how that goes.

You are correct, everything is from the same donor besides the ECM. I thought it had a problem right when I bought the donor. So I sent it in to zzp and they sent me out a new programmed one. What does the relearn entail?

 

[Briann1177]

Pretty sure it will require access to GM diagnostic tools.

 

[JPas914]

Briann1177 is correct, the clutch pedal possition sensor relearn will require the GM Tech2 tool. I had to have it performed on my Goblin.

 

[Mayor West]

Briann1177 is correct, the clutch pedal possition sensor relearn will require the GM Tech2 tool. I had to have it performed on my Goblin.

I'm in this same boat and I'm not happy about it. You can, however, still jumpstart the car by screwdrivering the starter poles with the ignition on.

 

[JPas914]

Have you tried reaching out to any local car groups in your area to see if someone might have one? That’s what I had done in North Dakota, and one of the techs at a local tire/service center was able to bring it by my apartment. It’s not a large piece of equipment, and the whole process takes 5 minutes...at most. Hook it up to the OBD2 port, follow prompts, turn off the car/disconnect tool, wait 30 seconds to a minute then fire up the car.

 

[Ark :D]

Is this also true for the brake position sensor?

Is the tool something only a Chevy dealer would have?

Inquiring minds want to know! I replaced both my sensors, not realizing I'd need to get a relearn done.

 

[Mayor West]

Have you tried reaching out to any local car groups in your area to see if someone might have one? That’s what I had done in North Dakota, and one of the techs at a local tire/service center was able to bring it by my apartment. It’s not a large piece of equipment, and the whole process takes 5 minutes...at most. Hook it up to the OBD2 port, follow prompts, turn off the car/disconnect tool, wait 30 seconds to a minute then fire up the car.

I haven't taken delivery of my kit yet but I didn't get around to doing that when I was disassembling my donor. I'll reach out to some folks on my various facebook groups to see about that when the time comes.

I was under the impression it had to have a computer attached to it to code? I've looked in to the 300$ chinese clones on amazon/ebay and thought about that for the sake of future items needing addressing but the more I researched the more I was worried I'd have to have the additional software that a GM laptop would have, outside of the tool itself. I'm not entirely well versed on what the tool does outside of the laptop itself.

 

[Mayor West]

Is this also true for the brake position sensor?

Is the tool something only a Chevy dealer would have?

Inquiring minds want to know! I replaced both my sensors, not realizing I'd need to get a relearn done.

Only if its a newer model that has the potentiometer(sp) sensor. The earlier ones had "on off" sensors.

 

[Briann1177]

Only if its a newer model that has the potentiometer(sp) sensor. The earlier ones had "on off" sensors.

I could be wrong, but I couldn't find anything in the brake pedal sensor replacement section of my '09 service manual that says you have to do a relearn. The clutch sensor replacement section definitely does mention it though.

 

[JPas914]

I don’t believe there is a relearn procedure for the brake pedal sensor. I’m not 100% sure what all is a part of the Tech2 setup, but it wasn’t much...a couple cables, an interface, and a computer module about the size of an ipad.

 

[Mayor West]

Yes, it's new model clutches only. My b.

 

[Ark :D]

Makes sense though, as the clutch pedal sensor is part of the equation in starting the car. It makes sense that they would bind it to the car, same as the key.

 

[Yustas]

3 wire brake pedal position sensor requires BCM relearn.