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roggy roo

ECU pinouts/ODB

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Trying to install LPG on my '02 525, need to tap into 4 lines to talk to ODB, K line, pin 7, L line pin 15, Can-l pin 14, Can-H pin6.

There's a connector under the dash, rather pointless tracking wires from the bay into the car, when I can just cross engine bay the LPG ECU to the Engine ECU.

Good source for the ECU pinouts anyone?

 

As an aside it only looks like 5 or 6 pins on the ODB connector are occupied looking at the contact pins, none are the one's I'm after anyway.

 

Oh, do these use a cam sensor, looking for a source for an RPM signal, otherwise I'll try using a coil earth line for the signal.

 

Edit: other thing I'd forgot.

 

Need to tap into the coolant lines to the heater for the vapouriser/reducer.

I see the Beemer has 3 coolant lines going into the bulkhead, 1 x 19 mill, and 2 x 16 mill (going by eye, didn't measure) why 3 coolant lines?

I'm assuming all of them are from the engine side of the thermostat, hot and flowing before the thermostat opens?

Edited by roggy roo

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CVhrlXu.gif

 

 

The K line is either 17 or 20...

Technically they are both the K line, but BMW do a thing where you have a K line to the engine and gearbox, and another one to the rest of the body modules. That's why you might see people mentioning bridging pins 7 and 8 on the 16 pin OBD connector to join those K lines to get talking to the complete car.

 

The L line would have been pin 15, but that's unlikely to have anything in it, the L line (called RXD) isn't used a lot these days. It was a wake-up signal, hence it is RXD for Receiving.

 

CAN might be on pins 2 and 3, but I imagine the LPG kit isn't going to need both CAN and K line, just one or the other should do, and your car would be classed as a "K line" car, so it does its diagnostics over that one wire.

 

 

Pin 1, TD, is an RPM pulse.

 

The coolant lines are likely to be 2 inputs , the smaller ones, for each side of the car, and one shared return so heating can be individually set for each side.

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Yes I'm the 16 pin connector under the dash, prefer not to cut into it there, it's a pita rolling around on the floor for one thing.

LPG ecu is going under the drivers side cabin filter, run the wires across the bay and cut into the ECU outputs there, is the plan.

 

OK I'll Tee off the heater lines engine side of the valves on the inner wing, should get good coolant flow there, based on my limited knowledge thermosyphon might help it flow too.

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CVhrlXu.gif

 

 

The K line is either 17 or 20...

Technically they are both the K line, but BMW do a thing where you have a K line to the engine and gearbox, and another one to the rest of the body modules. That's why you might see people mentioning bridging pins 7 and 8 on the 16 pin OBD connector to join those K lines to get talking to the complete car.

 

The L line would have been pin 15, but that's unlikely to have anything in it, the L line (called RXD) isn't used a lot these days. It was a wake-up signal, hence it is RXD for Receiving.

 

CAN might be on pins 2 and 3, but I imagine the LPG kit isn't going to need both CAN and K line, just one or the other should do, and your car would be classed as a "K line" car, so it does its diagnostics over that one wire.

 

 

Pin 1, TD, is an RPM pulse.

 

The coolant lines are likely to be 2 inputs , the smaller ones, for each side of the car, and one shared return so heating can be individually set for each side.

 

OK getting round to this eventually, found a blank punched in the bulkhead by the servo, knocked that out and fed the wires in there, just the right size for the LPG ecu's diagnostic connector too, very handy.

 

You were right pins 7 and 8 K line/s, nothing on 15, but 1, 4, 5, 9, 16 all occupied but nothing I can use.

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