doublekite2000

I bought a 2007 2.7D S Type about 3 months ago (78k miles). The service history mentions a parkbrake fault being investigated in 2013 and 2015, on both occasions HA Fox reset the system and stated a new parkbrake module would be needed if it happened again. No replacement parts were ever fitted. I have had intermittent problems with the same fault since purchase, and new rear brake pads and a new battery have not cured it. Recalibration done of course. The fault seems to be after driving the car from cold on short journeys of up to 5 miles, such as a school run. When returning to the car after, say, 15 minutes, the fault appears and is able to be cleared by disconnecting the battery for 10 seconds. My indy mechanic has put it on diagnostics and found the following fault codes: DTC ECU Description 1800-00 PBM Motor engage current reached before full apply travel distance 1802-00 PBM Motor engage current not reached or travelled too far on apply Now I'm no expert, but the above faults seem to be the opposite of each other, so whats going on? I am told there is no problem with the wiring or cables and that it may be the parkbrake module or the parkbrake motor but neither could be identified as definitely the culprit. So which part do I replace first?