How to determine wires on 3 wire VR sensor?
Forum rules
Read the manual to see if your question is answered there before posting. Many users will not reply if the answer is already available in the manual.
If your question is about troubleshooting, configuration, or tuning, you MUST include your processor type (MS-I or MS-II) and code version in your post. If your question is about PCB assembly or modifications, you must also include the main board version number (1.01, 2.2 or 3.0).
If you have questions about MS1/Extra or MS2/Extra code configuration or tuning, please post them at www.msextra.com Such questions posted here will be moved to: a temporary MSextra sub-forum, where they will be removed after 7 days
The full forum rules are here: Forum Rules, be sure to read them all regularly.
Read the manual to see if your question is answered there before posting. Many users will not reply if the answer is already available in the manual.
If your question is about troubleshooting, configuration, or tuning, you MUST include your processor type (MS-I or MS-II) and code version in your post. If your question is about PCB assembly or modifications, you must also include the main board version number (1.01, 2.2 or 3.0).
If you have questions about MS1/Extra or MS2/Extra code configuration or tuning, please post them at www.msextra.com Such questions posted here will be moved to: a temporary MSextra sub-forum, where they will be removed after 7 days
The full forum rules are here: Forum Rules, be sure to read them all regularly.
-
cahillicus
- MegaSquirt Newbie
- Posts: 23
- Joined: Thu Apr 14, 2005 5:33 pm
- Location: Nor-Cal
How to determine wires on 3 wire VR sensor?
My VR sensor has three wires. From what I have read, one is for 'shielding', but I don't know which is which. I tested all pin combos for continuity and resistance. None had continuity, and the only to that showed resistance were pins 2 & 3 (1.012kohm). Which wires get connected to what?
'81 Yamaha XS1100
MSII v3
Carb to FI Conversion
'03 GSX-R Throttle Bodies
GM DIS
MSII v3
Carb to FI Conversion
'03 GSX-R Throttle Bodies
GM DIS
Re: How to determine wires on 3 wire VR sensor?
If you found resistance between wire 2/3 then connect them on. if pin one has no resistance to the other 2 wires then this must be ground
-
timothyalderson
- MegaSquirt Newbie
- Posts: 3
- Joined: Fri Sep 05, 2008 11:38 pm
Re: How to determine wires on 3 wire VR sensor?
When you say VR. Do you mean VRS, Variable reluctance sensor?? If so I can tell you how to check it.
If the sensor is a VRs type,it will produce an Ac voltage in use. This type of sensor will have two or three wires going to the pcm or icm. The Ac voltage will exist between two of the three wires; the third is the shielding wire, and will be grounded somewhere. (Some types af VRS's are case grounded, which means sometimes in a schmatic it will show a third but when you look at the sensor you only see two.)In most cases the signal itself is not refrenced to ground. If you attempt to check for a signal with one lead of your DMM ( Digital Multi Meter, FLuke ETC...) or Oscilliscope connected to the ground and the other connected to a wire from the sensor, you may not read any signal, or the signal measured may show a much lower voltage than specified, causeing miss diagnosis or wiring problems.The propor connection is between the two signal carrying wires. The actual voltage reading on the DMM will depend on factors such as the DMM used, the engine speed, the air gap between the sensor and the reluctor, as well as the shape of the reluctor itself. a reluctor with many teeth will tend to produce a higher voltage readingon the DMM for two reasons.
1: The duty cycle of the signal will be higher with more teeth.
2: The DMM will display the average voltage measured.
So if your only looking for the proper way to wire the sensor then my best advise is to use a DMM adn check for polarity between all the wires the two that have polarity are the + AC adn -AC wires. those are the two you want to wire in to the PCM. The other is the shielding wire and just wire that one to the block. The problem you going to have is finding which one is the positive and negative. The best way to find that is to get a wiring diagram such as one from a Repair manual ( chiltons etc.) and find out what the wire colors are and go by that.
If the sensor is a VRs type,it will produce an Ac voltage in use. This type of sensor will have two or three wires going to the pcm or icm. The Ac voltage will exist between two of the three wires; the third is the shielding wire, and will be grounded somewhere. (Some types af VRS's are case grounded, which means sometimes in a schmatic it will show a third but when you look at the sensor you only see two.)In most cases the signal itself is not refrenced to ground. If you attempt to check for a signal with one lead of your DMM ( Digital Multi Meter, FLuke ETC...) or Oscilliscope connected to the ground and the other connected to a wire from the sensor, you may not read any signal, or the signal measured may show a much lower voltage than specified, causeing miss diagnosis or wiring problems.The propor connection is between the two signal carrying wires. The actual voltage reading on the DMM will depend on factors such as the DMM used, the engine speed, the air gap between the sensor and the reluctor, as well as the shape of the reluctor itself. a reluctor with many teeth will tend to produce a higher voltage readingon the DMM for two reasons.
1: The duty cycle of the signal will be higher with more teeth.
2: The DMM will display the average voltage measured.
So if your only looking for the proper way to wire the sensor then my best advise is to use a DMM adn check for polarity between all the wires the two that have polarity are the + AC adn -AC wires. those are the two you want to wire in to the PCM. The other is the shielding wire and just wire that one to the block. The problem you going to have is finding which one is the positive and negative. The best way to find that is to get a wiring diagram such as one from a Repair manual ( chiltons etc.) and find out what the wire colors are and go by that.