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"Wrench" warning light

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Hi all,

Maybe there is a thread for this already, but I haven't found it. My 2017 GT350 gives me a "wrench" light with the message "See manual". I can't find any wrench symbols in the manual. It clears after the car is shutdown and leaves no code. When the light comes on (after 30-60 minutes of driving), the cruise control stops working. Otherwise, all seems fine.

My engine is stock with the exception of a JLT CAI and JLT tune. The car has 5500 miles with several track days and auto-crosses.

Anyone know what is going on with this one?

Thanks!
 
There could be many reasons for the code, if you can find a scanner it will tell you what the code is for.
 
I failed to properly heat up the motor at a track day (didn't have oil temp to 200F), the car limited rpm's to 7500, showed the wrench then cleared when the car was turned off. Next session it was like normal. I drive a '17 gt350
 
The tune likely optimizes whp and torque and ignores a bunch of other functions. Plug in your tune hardware, return to stock, and see if it goes away.
If it does, JLT propeller heads should interrogate your car ( after you plug it back in and restore tune, reproduce driving conditions, and throw another wrench light.)
and fix it.
MY tune ( Paramount Speed/ Palm beach Dyno) added 20 whp/ 20 ft lbs torque, but car is jumpy and stutters when cold, and it wouldn't smog because tune software erases the "black box" in favor of maxing out the ponies for tracking. I drive my car stock, and return programming to tune when tracking...
 
Turns out my Autoblip was interfering with the clutch position sensor. After disconnecting the Autoblip, the problem went away.


Sent from my iPhone using Tapatalk
 

steveespo

Lord knows I'm a Voodoo Child
Moderator
4,008
1,924
Exp. Type
W2W Racing
Exp. Level
10-20 Years
Cookeville TN
Hi all,

Maybe there is a thread for this already, but I haven't found it. My 2017 GT350 gives me a "wrench" light with the message "See manual". I can't find any wrench symbols in the manual. It clears after the car is shutdown and leaves no code. When the light comes on (after 30-60 minutes of driving), the cruise control stops working. Otherwise, all seems fine.

My engine is stock with the exception of a JLT CAI and JLT tune. The car has 5500 miles with several track days and auto-crosses.

Anyone know what is going on with this one?

Thanks!
Wrench light is specifically related to throttle body calibration. If the commanded position and actual position don't agree within .5 degree wrench light will illuminate and put the car in limp mode. I am not aware of the light coming on without reducing power.
 
Wrench light can also be caused by issues with pedal switches or Magneride. It's sometimes accompanied with either a (delayed) Hill Start Assist or Cruise Control not available message. I had a Wrench light and Hill Start assist caused by a Stop light switch failure (turns out the switch has two switches/circuits, one used for brake lights, the other for Hill Start/Cruise, only the latter had failed). Magneride failure will set limp mode and eliminate ability to change drive modes.

Most Wrench light conditions will reset on key-off. Some require battery power to be disconnected.
 

steveespo

Lord knows I'm a Voodoo Child
Moderator
4,008
1,924
Exp. Type
W2W Racing
Exp. Level
10-20 Years
Cookeville TN
Wrench light can also be caused by issues with pedal switches or Magneride. It's sometimes accompanied with either a (delayed) Hill Start Assist or Cruise Control not available message. I had a Wrench light and Hill Start assist caused by a Stop light switch failure (turns out the switch has two switches/circuits, one used for brake lights, the other for Hill Start/Cruise, only the latter had failed). Magneride failure will set limp mode and eliminate ability to change drive modes.

Most Wrench light conditions will reset on key-off. Some require battery power to be disconnected.
Thanks for additional insight Nick. I have been reading through the 2018 Diagnostics manual and the interaction with all of these systems has multiplied 4 fold over the S197. There are 4 High Speed Can buses in an S550, 1 in the S197.
 
Yes, 4 CAN busses (3 High speed, 1 Medium speed) and a gateway module to translate info between busses and to the OBD port.

Not many aftermarket diagnostic tools will correctly read all data other than CAN bus 1, which is mainly PCM info. Even some versions of ProCal will not read ABS, Power Steering and other modules on multi bus systems.

I’ve found FORScan Lite to be the most comprehensive diagnostic and logging tool.
 

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