Not a duplicate of When to go missed on a non-precision approach? please read carefully before duplicating this contains some subtle points. Reposting after clarifications that emphasise this is a different question
According to AIM 5.4.21 (b): When an early missed approach is executed [...] fly the IAP as specified on the approach plate to the MAP at or above the MDA or DH before executing a turning maneuver.
Hence if a pilot decides on a missed approach, he needs wait until over the MAP to execute any turns of that procedure. One can only assume that is meant to prevent a climbing turn into a nearby protected airspace.
The following scenario puzzles me.
A pilot executes a LOC approach with a missed approach consisting of "Climb to 1000' then left climbing turn to 5000' direct to..." Sometime after the FAF the cockpit timer breaks. The MAP can no longer be identified by time. The pilot immediately starts climbing to 1000'. But when to start the left climbing turn to 5000'?
The aircraft does not have other equipment that would positively identify the MAP, when is that pilot required to begin that turn?
The aircraft has a DME and a functioning timer? Which is preferred to identify the MAP? Is the pilot allowed to change from timer to DME after having initially started using the timer for MAP identification upon timer becoming unusable or does equipment malfunction mandate execution of a missed approach?