In this paper we introduce the method for investigation of coupled chaotic
systems using topological methods. We show that if the coupling is small th
en there exists independent symbolic dynamics for every coupled subsystem a
nd in consequence the systems are not synchronized. As an example we consid
er coupled Henon maps. Using computer interval arithmetic we find parameter
mismatch and perturbation range for which the symbolic dynamics in the Hen
on system is sustained. For coupled Henon maps we compute the value of coup
ling strength for which the symbolic dynamics in every subsystem survives.