Fitting PLX R500 Wideband
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From: Sunshine Coast - England UK
Fitting PLX R500 Wideband
Hi all,
I need to put the 20 ohm 10W resistor across the O2 heater +ve and -ve terminls but not sure which ones they are?
Im pretty sure connector C pin 1 is +ve but cant see its ground reference on the ECU diagrams.
Help appreciated!
MB
I need to put the 20 ohm 10W resistor across the O2 heater +ve and -ve terminls but not sure which ones they are?
Im pretty sure connector C pin 1 is +ve but cant see its ground reference on the ECU diagrams.
Help appreciated!
MB
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From: Johannesburg/ZA
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From: Sunshine Coast - England UK
Hi, looked at that one but going to the fuse box doesn't seem right to me. Both the wires are at the ECU somewhere.
I may just use a multimeter on the end of the plug and mount the resistor there. It can get a bit hot so probably best leave it in the engine bay!
MB
I may just use a multimeter on the end of the plug and mount the resistor there. It can get a bit hot so probably best leave it in the engine bay!
MB
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C1 is pulled to ground (-ve) when the heater activates.
The positive for the Heater is taken from fuse 6 (BLK/Yellow) wire
Edit : Added the following
The reason it is done this way is to make the wiring less complicated, protect the ECU from shorts and make the fuse setup less complicated (easier to do fuse per circuit).
Eg,
wire from the Fuse to 02 Heater shorts (+ve) blows fuse ECU == OK. Wire from 02 Heater shorts ECU pulling to gnd (-ve) no damage done ECU == OK.
The positive for the Heater is taken from fuse 6 (BLK/Yellow) wire
Edit : Added the following
The reason it is done this way is to make the wiring less complicated, protect the ECU from shorts and make the fuse setup less complicated (easier to do fuse per circuit).
Eg,
wire from the Fuse to 02 Heater shorts (+ve) blows fuse ECU == OK. Wire from 02 Heater shorts ECU pulling to gnd (-ve) no damage done ECU == OK.
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From: Sunshine Coast - England UK
Sorry for being thick here, but do I need to link C1 pin1 with fuse 6??
As mine is a UK car, the ECU is on the passenger side and the fuse box is on the right.
Help!
MB
As mine is a UK car, the ECU is on the passenger side and the fuse box is on the right.
Help!
MB
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Joined: Apr 2004
Posts: 33,838
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From: Sunshine Coast - England UK
Im thinking doing it at the connector is going to be easier to complete the circuit?
Edit - those 101 / 404 connectors arent at the fuse box, I think they live next to the ECU regardless of RHD or LHD - will try and look tomorrow!
MB
Edit - those 101 / 404 connectors arent at the fuse box, I think they live next to the ECU regardless of RHD or LHD - will try and look tomorrow!
MB
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The 101/404 connectors are fed from Fuse 6 ( BLK/YEL Wire)
You need to connect C1 via your 20 Ohm resistor to 101 or 404 (BLK/YEL Wire)
101 / 404 will have power (+ve), C1 effectively switches to ground to complete the circuit and heat the resistor (or O2 heater normally).
Edit : Fixed resistance should have read 20 not 10 and added ref to BLK/YEL wire
You need to connect C1 via your 20 Ohm resistor to 101 or 404 (BLK/YEL Wire)
101 / 404 will have power (+ve), C1 effectively switches to ground to complete the circuit and heat the resistor (or O2 heater normally).
Edit : Fixed resistance should have read 20 not 10 and added ref to BLK/YEL wire
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