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12:th-Mar-2018, 11:20:41
This is what i know about the MERIVA's towbar wiring... using that trailer interface module you have (TIM) there's basically about 4 wires that need connecting to the car and 3 earths,
one wire is to the brake light wire on the car... might not be needed on astra's.. on merivas the brake light isnt on the canbus it seems... it's also able to be controlled by other modules directly, hence the need to tap into it.
Then there's a couple of power wires, one to run the TIM,
the other to feed power to the 13 pin trailer socket... for power to charge a caravans battery and run the fridge etc, that looks to be those thick red and yellow wires with the white plug going to the trailer socket.
Then there's a wire to the front of the car (meriva's dont have rear electrical centres like astras do) that wire is the canbus wire, so basically one connection runs all the lights on the trailer, gives you bulb out warnings and aparantly alters the abs and eps when towing... if towing a caravan and it gets into a snake, the car will brake the opposite rear wheels to try and correct the snake before the caravan flips the car over or spins it around,
Oh, and if you have rear reversing sensors, it turns them off when towing too... BUT, it needs programming to the car with a tech2/mdi, simple 5 minute job to tell the bcm and reversing sensor module that you now have a trailer interface.
personally i'd wire in the TIM you have, as it integrates the trailers lights into the car, and is only a few connections, and the canbus connection will be at the rear electrical centre, so easier than on a meriva.
to use a canbus bypass module you will need 6 or 7 connections to the rear lights, power, earth, and an annoying buzzer that goes off when the trailers indicators are working (with the factory system, it tells you if you have a trailer bulb out rather than buzzzing or a second indicator symbol on the dash)
The wiring connections can be worked out, may need a bit of a new loom making up... and i dunno why they cut the main (big red) power tire to the TIM.. and so close to the plug,
one wire is to the brake light wire on the car... might not be needed on astra's.. on merivas the brake light isnt on the canbus it seems... it's also able to be controlled by other modules directly, hence the need to tap into it.
Then there's a couple of power wires, one to run the TIM,
the other to feed power to the 13 pin trailer socket... for power to charge a caravans battery and run the fridge etc, that looks to be those thick red and yellow wires with the white plug going to the trailer socket.
Then there's a wire to the front of the car (meriva's dont have rear electrical centres like astras do) that wire is the canbus wire, so basically one connection runs all the lights on the trailer, gives you bulb out warnings and aparantly alters the abs and eps when towing... if towing a caravan and it gets into a snake, the car will brake the opposite rear wheels to try and correct the snake before the caravan flips the car over or spins it around,
Oh, and if you have rear reversing sensors, it turns them off when towing too... BUT, it needs programming to the car with a tech2/mdi, simple 5 minute job to tell the bcm and reversing sensor module that you now have a trailer interface.
personally i'd wire in the TIM you have, as it integrates the trailers lights into the car, and is only a few connections, and the canbus connection will be at the rear electrical centre, so easier than on a meriva.
to use a canbus bypass module you will need 6 or 7 connections to the rear lights, power, earth, and an annoying buzzer that goes off when the trailers indicators are working (with the factory system, it tells you if you have a trailer bulb out rather than buzzzing or a second indicator symbol on the dash)
The wiring connections can be worked out, may need a bit of a new loom making up... and i dunno why they cut the main (big red) power tire to the TIM.. and so close to the plug,
