Help! DIY 4 amp L297/6203 driver

[Ross77]

Thanks for the input, most appreciated.

The mono stable and astable idea sounds good but beyond my capabilites so I will have to wait for your input
I found a circuit that uses a 555 to pull vref down after 10s, its from a unipolar design that uses an L297 so i presumed it would be ok.

I'm not sure if I fully understand the timing delay, I presumed that the control circuit would activate the lower vref so soon as the clock stopped? but looking at this I think it only works after 10s of inactivity. so in most cases the current will be full power?