Oil Pressure Light - and then, not
HDF Community Team
Joined: Mar 2017
Posts: 7,824
Likes: 4,383
From: Texas
Logically that makes no sense, since nothing other than the fuel pump is affected by what youre describing. I wonder why your oil light comes on.
Tourer
Joined: Apr 2019
Posts: 270
Likes: 226
From: DFW Area
The only thing that I can think of for that scenario might be shut down sequence of the ECU. Perhaps there is a delay in the sequence to get shutdown completely done and ready for a restart. I could also be that Im full of !@#$, just thinking out loud
Stellar HDF Member
Joined: Jan 2017
Posts: 2,662
Likes: 2,065
From: Massachusetts
Weird you got a high and low oil pressure code when that bike doesn't have an variable oil pressure sender. Its only equipped with a switch that is either good or no good on pressure.
Intermediate
Joined: May 2009
Posts: 37
Likes: 3
I'm wondering if this has to do with starting off quickly without the bike going through all the checks. The oil light seems to be the last light that goes off after the other lights go off when starting the bike!
HDF Community Team
Joined: Mar 2017
Posts: 7,824
Likes: 4,383
From: Texas
Where are you getting this information?
Seasoned HDF Member
Joined: Jan 2006
Posts: 11,467
Likes: 2,996
From: Charleston, SC
From the first post.
Take in mind, the ECM usually talks to it's sensors with 5 volts and a resulting, variable, voltage drop depending on what the sensor is doing.
If the sensor looses connection it might be read by a "high" voltage thus leading to a P0523 and when it's suddenly reconnected sees a low voltage and maybe P0522.
Totally spit balling and I might have them reversed. I forget.
If the sensor looses connection it might be read by a "high" voltage thus leading to a P0523 and when it's suddenly reconnected sees a low voltage and maybe P0522.
Totally spit balling and I might have them reversed. I forget.
Last edited by lp; Oct 7, 2019 at 01:06 PM.
HDF Community Team
Joined: Mar 2017
Posts: 7,824
Likes: 4,383
From: Texas
From the first post.
Take in mind, the ECM usually talks to it's sensors with 5 volts and a resulting, variable, voltage drop depending on what the sensor is doing.
If the sensor looses connection it might be read by a "high" voltage thus leading to a P0523 and when it's suddenly reconnected sees a low voltage and maybe P0522.
Totally spit balling and I might have them reversed. I forget.
Take in mind, the ECM usually talks to it's sensors with 5 volts and a resulting, variable, voltage drop depending on what the sensor is doing.
If the sensor looses connection it might be read by a "high" voltage thus leading to a P0523 and when it's suddenly reconnected sees a low voltage and maybe P0522.
Totally spit balling and I might have them reversed. I forget.
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Seasoned HDF Member
Joined: Jan 2006
Posts: 11,467
Likes: 2,996
From: Charleston, SC
I thought in the switch there was a resister in parallel with the two wires or something that provides a less than 5 volt and greater than 0 volt reading so the ECM would know it's connected.
If the switch was Open, the line/ECM would read 5 volts (PO522). If shorted, 0 volts (P0523). Normal pressure, say 2 volts, and if low pressure, say 4 volts.
Something like that. Like I said, spit balling.
Last edited by lp; Oct 7, 2019 at 02:13 PM.
Seasoned HDF Member
Joined: Aug 2017
Posts: 7,323
Likes: 11,757
From: Omaha,NE
From the first post.
Take in mind, the ECM usually talks to it's sensors with 5 volts and a resulting, variable, voltage drop depending on what the sensor is doing.
If the sensor looses connection it might be read by a "high" voltage thus leading to a P0523 and when it's suddenly reconnected sees a low voltage and maybe P0522.
Totally spit balling and I might have them reversed. I forget.
Take in mind, the ECM usually talks to it's sensors with 5 volts and a resulting, variable, voltage drop depending on what the sensor is doing.
If the sensor looses connection it might be read by a "high" voltage thus leading to a P0523 and when it's suddenly reconnected sees a low voltage and maybe P0522.
Totally spit balling and I might have them reversed. I forget.
Open = open switch = high
Low and high are referring to reference voltage, not oil pressure.