mercedes w123 rear right power window

There are two items to check. First be sure the rear-window push-push safety switch is not activated. It is located in console next to driver's-side window switches. Purpose is to disable both rear door switches operation. If the safety switch is not depressed, inadvertent operation of the rear door windows (for instance, by children) is prevented (quoting the Owner's Manual). Both rear windows are affected when safety switch is enabled. Second, and typically affecting just one door, is broken wiring in the flexible conduit. The rubber tubing between jamb and door contains wires. Repeated flexing as door is opened and closed causes chafing and may lead to eventual failure. Carefully remove conduit at one end, then inspect wires for damage. Failure of the flexible conduit (cracking, tearing, punctures, etc.) accelerates wear of the wiring due to moisture intrusion and foreign matter accumulation (dust, grit, etc.). Repair wiring as required. Seal minor damage to flexible conduit with silicone sealer or equivalent. Significant damage to flexible conduit mandates replacement of the part.