Whats the Pefered Method to Wire for Voltage Dist?
Whats the Pefered Method to Wire for Voltage Dist?
(OP)
I have a new ECU that I'm wiring to an engine with a significant number of sensors. Each 3 wire) sensor needs to be supplied with a 5v signal from the ECU. Since I cant wire them all individually in to the one output pin of the ECU, what would be the simplest method for connecting them all? I'm hesitant to run a wire all the way to each sensor and tie the in to common block fed by the ECU as that doesn't seem too elegant. I guess I could piggy back with the lead going to one sensor then another and so on and so forth. Is there a common practice?
thanks
thanks





RE: Whats the Pefered Method to Wire for Voltage Dist?
Don't you have install instructions for this new ECU? If it's an aftermarket unit it should have very well detailed instructions.
RE: Whats the Pefered Method to Wire for Voltage Dist?
Regards
Pat
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RE: Whats the Pefered Method to Wire for Voltage Dist?
A decent, low resistance connection to each sensor will ensure long-term reliability and robust engine operation.
One of the issues sometimes seen on systems where the OEM has skimped on the vehicle wiring is the gradual increase in connector contact resistances, added to scrawny wiring resistance, giving the 5V regulator in the ECM drop-outs during cranking, which may then corrupt signals from sensors that contain electronics/ASICs which may depend on the 5V regulated supply for plausible outputs. Things like Hall effect cam and crank sensors, for example. Corruption of these signals will probably prevent a start.
Bill
RE: Whats the Pefered Method to Wire for Voltage Dist?
RE: Whats the Pefered Method to Wire for Voltage Dist?
Bill
RE: Whats the Pefered Method to Wire for Voltage Dist?
In addition - The 5V output from the ECU should have a maximum rating (probably reported as maximum amps). Do not exceed this. Each of your sensors will consume some amount of power. You can power multiple sensors as long as their current consumption does not exceed the rated output of the 5V channel (Most 3 wire sensors consume very little power - but also most 5V references are only good to about 1 amp - on stock OEM ECU's). If the ECU has multiple 5V references, divide the sensors up logically between them.
RE: Whats the Pefered Method to Wire for Voltage Dist?
a) Consider signals present , if any of the sensors produce small signals , screening and routing these away from High Current wiring produces a more tollerant design.
The above may not be true with modern sensors .
b) Unexpected grounds may produce ground loops and strange DC
offsets when starter engaged !
Some sensors are less important than others , a full undersatnding ot the function of each sensor may help in chosing its importance .