OIL Temp Circuit Problem
Thread Starter
Racer
Joined: Aug 2008
Posts: 493
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OIL Temp Circuit Problem
So my oil temp was reading "Low oil temp". I decided to just replace the sensor since it was only 15 bucks, but that didn't fix it. I am getting a code b1543. What types of things can I check? I am going to check the harness for 5v and ground continuity. If I find a problem, what are common weak points to check?
Tech Contributor
Joined: Jan 2007
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From: Dyer, IN
So my oil temp was reading "Low oil temp". I decided to just replace the sensor since it was only 15 bucks, but that didn't fix it. I am getting a code b1543. What types of things can I check? I am going to check the harness for 5v and ground continuity. If I find a problem, what are common weak points to check?
Tech Contributor
Joined: Jan 2007
Posts: 19,360
Likes: 1,127
From: Dyer, IN
Thread Starter
Racer
Joined: Aug 2008
Posts: 493
Likes: 2
lol, I know, I'm on my way to grab some batteries for my multimeter. I just am afraid the wire is going to be severed in some random hard to get to location. I'll let you know what I find out with the meter
Tech Contributor
Joined: Jan 2007
Posts: 19,360
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From: Dyer, IN
Provided that you are checking with the key on...inspect the connector for corrosion. Verify you have a good reference ground for when checking voltage. Tug on the wires in the connector to make sure they are not broken at the strain relief. If all looks good, start tracing that harness..and inspect for damage.
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Thread Starter
Racer
Joined: Aug 2008
Posts: 493
Likes: 2
Okay, I am trying to understand this diagram. Does this mean the oil temp sensor doesn't connect to the PCM? Does it go to the BCM? Or does it just go to the DIC? Is there a fuse anywhere that I should check? I really don't feel like disconnecting all the connectors and pulling the loom out from behind the engine......is there a better way to follow these two wires? Honestly I can't see only this wire getting damaged in the loom behind the engine....I'm guessing the problem is somewhere else, so if I can find the other end of the wire, I would have a another starting point to work from.
Tech Contributor
Joined: Jan 2007
Posts: 19,360
Likes: 1,127
From: Dyer, IN
Okay, I am trying to understand this diagram. Does this mean the oil temp sensor doesn't connect to the PCM? Does it go to the BCM? Or does it just go to the DIC? Is there a fuse anywhere that I should check? I really don't feel like disconnecting all the connectors and pulling the loom out from behind the engine......is there a better way to follow these two wires? Honestly I can't see only this wire getting damaged in the loom behind the engine....I'm guessing the problem is somewhere else, so if I can find the other end of the wire, I would have a another starting point to work from.
Thread Starter
Racer
Joined: Aug 2008
Posts: 493
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Okay, I checked from the sensor, to the c102 connector that comes out of the fuse box....it didn't appear that there was continuity. There isn't a relay/fuse in the fuse box I need to worry about is there? Is it safe to say the wire is damaged...if it means anything, I didn't have continuity on the ground or the 5v
Tech Contributor
Joined: Jan 2007
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From: Dyer, IN
Okay, I checked from the sensor, to the c102 connector that comes out of the fuse box....it didn't appear that there was continuity. There isn't a relay/fuse in the fuse box I need to worry about is there? Is it safe to say the wire is damaged...if it means anything, I didn't have continuity on the ground or the 5v
Tech Contributor
Joined: Jan 2007
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From: Dyer, IN
The ground(low reference) is provided directly from the IPC, so checking the resistance to the engine block does not check the continuity of the wire itself.
Thread Starter
Racer
Joined: Aug 2008
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Is the 5v From the ipc as well. If I connect my battery , I should have 5v from the firewall side? Is my assumption correct that I should have continuity from the green wire at the sensor plug, to the green wire on the c120 plug(fusebox side)? Thanks for your help here...I think were close here
Tech Contributor
Joined: Jan 2007
Posts: 19,360
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From: Dyer, IN
Is the 5v From the ipc as well. If I connect my battery , I should have 5v from the firewall side? Is my assumption correct that I should have continuity from the green wire at the sensor plug, to the green wire on the c120 plug(fusebox side)? Thanks for your help here...I think were close here
Thread Starter
Racer
Joined: Aug 2008
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Thanks for the help so far. Here is where I am at. I had 3.8 volts at the plug going into the firewall, so all appears good there. I rechecked the wires to the sensor plug, and the reference wire checked good this time, but the 5v still isn't showing continuity. I guess its time to pull these wires out, can you post a diagram of the sensor wire and the correct loom? Also, are the wires usually taped together in the loom, or can I just pull the two wires I need out of the loom? Thanks in advance,
Tech Contributor
Joined: Jan 2007
Posts: 19,360
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From: Dyer, IN
Thanks for the help so far. Here is where I am at. I had 3.8 volts at the plug going into the firewall, so all appears good there. I rechecked the wires to the sensor plug, and the reference wire checked good this time, but the 5v still isn't showing continuity. I guess its time to pull these wires out, can you post a diagram of the sensor wire and the correct loom? Also, are the wires usually taped together in the loom, or can I just pull the two wires I need out of the loom? Thanks in advance,
Thread Starter
Racer
Joined: Aug 2008
Posts: 493
Likes: 2
Problem solved, thanks for all your help.
I started tracing the wire from the plug, and followed it under the fuse box through the looms...and back out into another plug..a around plug, which is where I found the damage to the wire
It sucks, because it wasn't so hard to find, but I guess when you don't know where to look, things are hard to find....so thanks for giving me a good starting point. Not sure what caused this, but I fixed it up, taped it up, and tucked everything neatly away.
Now, I have 3.8 volts or so at the plug (car not running). When I plugged the sensor back in, it said oil temp 33 degrees...which can't be right. So I took the keys out, unplugged it, and attached the old sensor, put they key back in, and it said low oil temp..then when I plugged the new one in..and it said low oil temp.
I reset all the codes...do I just need to drive this for a while to get it working right again? Like I said, I have the voltage at the sensor, and its a brand new sensor....
I started tracing the wire from the plug, and followed it under the fuse box through the looms...and back out into another plug..a around plug, which is where I found the damage to the wire
It sucks, because it wasn't so hard to find, but I guess when you don't know where to look, things are hard to find....so thanks for giving me a good starting point. Not sure what caused this, but I fixed it up, taped it up, and tucked everything neatly away. Now, I have 3.8 volts or so at the plug (car not running). When I plugged the sensor back in, it said oil temp 33 degrees...which can't be right. So I took the keys out, unplugged it, and attached the old sensor, put they key back in, and it said low oil temp..then when I plugged the new one in..and it said low oil temp.
I reset all the codes...do I just need to drive this for a while to get it working right again? Like I said, I have the voltage at the sensor, and its a brand new sensor....
