If you dig out a wiring diagram you will find the ECS is fed by a Red wire that is live in ACCY and Run. Look in that wiring loom along the bulkhead for a Red wire as it feeds several things in the engine bay from the fuse box down a red wire.
The Manifold heater is fed by a relay. The control side comes from the ECS. The power for the heater itself comes from a splice into the large red wire that runs from the solenoid up to the bulkhead and eventually feeds the fuse box.
You therefore need to locate the Manifold Heater Relay and check how it is wired.
BagusJeep lives in Bali.
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