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Tech question re Lambda sensors? - Pete
Anyone out there with knowlege of Bosch Lambda's please?

LSH6 is three wire, LSH15 is four wire. Externally, the sensor units appear identical.

Question. Is it simply that the LSH15 has the fourth (earth) wire and that the units themselves ( internals, values etc ) are the same ?

Any input/confirmation will be much appreciated.
Thank you, Pete. petel@clara.co.uk
Tech question re Lambda sensors? - David Davies
Pete
Yes they are probably basically the same sensor,but I don't think you could replace a 4 wire type with a three wire as the fourth(usually grey) wire goes to a dedicated earth point inside the engine ECU.IN fact the current thinking in the trade is that its best to avoid universal lambda sensors altogether and only use OE sensors or a specific replacement part from Bosch or NGK.This is particularly true of Rover applications.Is there any particular car or problem that you have in mind? t
David Davies (Tune-Up Raglan)
Tech question re Lambda sensors? - Pete
Thanks for your reply Mr Davis.
I have seen several references to the avoidance of "universal" sensors, one on this forum.
Would still be interested if anyone can provide positive confirmation of the similarity of internals/values of the Bosch sensors, or any other manufacturer for that matter.
Thank you, Pete.
Tech question re Lambda sensors? - Andy P
The most common type of Lambda sensor is called the Zirconia type. It is a resistive-type sensor which requires a voltage input to allow it to give an output which is related to the oxygen content of the exhaust. The sensors can have up to four wires:

Single wire - signal only with internal ground
Two wires - signal + ground
Three wires - heated type. Signal, heater and heater ground
Four wires - heated type. Signal, heater, heater ground and sensor ground

The other lambda sensor is called the Titania type. It has three of four wires:

Three wire - signal in from ECU, signal out to ECU and ground wire
Four wires - heated type. Signal in from ECU, signal out to ECU, heater supply and heater ground.

You can't interchange the two types, and you can't replace a four-wire with a three wire, since the ECU would not receive a ground signal.

Hope this helps.


Andy
Tech question re Lambda sensors? - Pete
Hello Andy.
Thanks for your most informative reply. I have taken a hard copy for my files.

Rgds, Pete.
Tech question re Lambda sensors? - Pete
Still hoping that someone out there can answer the original question. Anyone please?
Thanks, petel@clara.co.uk