I am not sure how this happened but it appears it may have taken out the circuit board of the cluster or the PCM. The speedometer is operated by the cluster taking the vehicle speed sensor from the PCM and displaying it. The fuel economy is just an average based on info from the IPC and PCM and the remote start has a lot of inhibit parameters from the IPC and PCM.
I would suggest starting with checking for codes. I am not sure how just jumping from the battery would cause this unless they hooked the cables up backwards. The reason is, when you use the auxiliary location and not directly to the battery they are just cables that run to a more convenient location which gives better access.
I would suggest starting with the codes and going from there. Thanks
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Sunday, December 29th, 2019 AT 4:28 PM