It was not intended to reconnoitre and report as its name suggests but was a light armoured combat vehicle, mostly without a radio and used as a support tank for the mechanised infantry.

In the middle of February 1934, he sent the first, N° 79759, to the testing commission, after it had been lengthened and refitted with a much more powerful Nerva Stella 28 CV engine in September 1933,[1] which now was placed at the back, instead of the front, of the vehicle.

Renault was hesitant to introduce such expensive improvements in the production run; but, in February 1934, the head of the French Cavalry, General Flavigny, insisted on these changes being made.

However, some cavalry officers pointed out that the Renault Nerva Stella was a sports car and its engine rather delicate and thus unsuited to the rigours of military service.

The remaining eighty vehicles were to have a larger AVIS-2 turret with a 13.2 mm machine gun; 31 of the latter were also intended to be equipped with ER1 radio sets, though in 1937 it was decided to abandon this plan.

The onset of production was also slowed by coordination problems with the subcontractors: Schneider would produce the armour plates and construct empty hulls; Batignolles-Châtillon would make the AVIS-2 turrets.

Many mechanical parts proved to be too weak; especially the Cleveland differentials, which were not capable of taking the stress loads caused by the tank's high speed.

The AMR 35 vehicles remained very unreliable: on 1 January 1939, only 129 chassis of all subtypes were present in the combat units,[7] the others being centrally repaired or having been sent back to the factory.

On 16 November 1938, he begged the government to be exonerated from the contractual fines, pointing out that he had already, on his expense, twice completely replaced the gear wheels on all vehicles and additionally all transmissions and front axles.

The decision to design two types, despite the very small production batches, was motivated by the desire to let them operate in pairs; the low inconspicuous self-propelled gun would directly ambush enemy vehicles and the higher tank, fitted with a radio set, would be further back in an oversight position and, with its rotatable turret, covering the flanks.

This heavier type was produced parallel to the 7.5 mm machine-gun vehicles of the first production batch in a quantity of eighty; it was originally seen as the normal combat version, four of which would be present in a platoon of five.

However, given the absence of a turret, there was no need to wait for its development: Renault was instructed to quickly construct a first vehicle by adding a boiler plate superstructure to the old third AMR 35 prototype, and then sent it to Rueil where a gun could be built in and a cast commander cupola fitted.

APX indicated on 6 April 1936 — the plan to build just a single prototype already having been discarded when the second order was placed — that it desired to have five vehicles ready for the September manoeuvres of 1936.

Meanwhile, between April 1936 and July 1937, Renault and the French government had had a major disagreement over the question which company should be given the order to supply the cast cupola; eventually, this would be Batignolles-Châtillon.

To create sufficient room within the ZT 3, the hull was raised somewhat; the roof plates on the sides and front sloped towards the apex of the vehicle where a cast rotatable cupola provided the commander some height to observe his surroundings, in what was otherwise a very low and sleek construction.

In the front of the "turret" was a small gun mantlet that normally lacked any armament but in an emergency situation could be fitted with the portable FM 24-29 machine-gun that was part of the crew equipment.

The first vehicle used two ER29 sets; the others, conforming to a decision already made in 1936, used a combination of the ER29 and the ER26 ter; in the latter case, the effort to remain inconspicuous was rather spoiled by a very prominent large horizontal radio antenna frame fitted on top of the "turret".

General Darius Bloch, head of the technical section of the supreme command, had formed a favourable opinion on these in September 1933 and during a session of the Conseil Consultatif de l'Armement in January 1934 had desired that a dozen be acquired.

The delay of three years could not entirely be blamed on Renault: the different Arms for which the YSs were intended each had special requirements for the combinations of (short and long range) radio sets to be built in.

Of the ten, the Cavalry received four vehicles (reduced from an original planned allocation of six) using the so-called "Type C" equipment: a combination of the ER (Émitteur-Recepteur)26 ter and the ER29.

The two others used a "Type E" equipment with a combination of the ER 26 ter and the R15; these were assigned to mechanised infantry units, the 5e and 17e BCP (Bataillon de Chasseurs Portés).

On 11 August Renault was contacted to build a full scale wooden mock-up of a vehicle capable of accommodating the ER26 ter and R14 radio set, a large number of telephone cable connections and on top an optical rangefinder turret with a base of 160 centimetres.

On 2 April, a commission of artillery officers visited Renault and these suggested to use the smaller standard rangefinder used by machine-gun units that had a base of 125 centimetres.

Though Renault now had sufficient production capacity, the standard AMR 35 order having been finished, the labour and financial problems with his factory, combined with a lack of funding by the government, prevented any ZT 4 manufacture from starting.

After the German invasion, an emergency plan was considered to equip them with a 25 mm gun; in the end, some were sent to the front in June armed only with a makeshift machine-gun mount and others remained at the factory.

In 1936, the French Army began planning to execute, in case of a war with Germany, offensive airborne operations on the enemy flanks (Netherlands, Switzerland) or hinterland.

The other AMR 35s however, were to the contrary originally intended to be part of the main force and functioned as its, "first contact", direct security screen: this was at the time the meaning of reconnaissance in the French Cavalry doctrine.

Even this task, however, would later become secondary to what was to be the AMR's main function: to provide direct fire support to dismounted cavalry or mechanised infantry units; the armoured trucks used by the latter had not even a machine-gun armament.

However, in 1936, it was decided to redirect the production of the Hotchkiss H35, an infantry light tank that had been rejected by the Infantry in favour of the Renault R35, towards the Cavalry that decided to use it instead of the AMR 35 in the RRCs, even though the H 35 was not very fast: the AMR 35's poor armour weighed very heavily against it as the French military in this period became increasingly convinced that lightly armoured vehicles could not survive on the modern battlefield.

A certain number (circa twelve including at least one mortar-equipped vehicle) were used by Panzerkampfwagen-Kompanie 539 in Prague for occupational duty in the protectorate of Böhmen und Mähren.