How to replace the coolant temperature sensor for ECU/dash on a BEW:
***
I had a CEL light that was intermittent and the idle would vary from 900 to 1100 rpm. Talked with B2P and we used his VAG-COM to check the fault code. The fault code P0118 was found. The dash temperature was 90C and the ECU was seeing –4C. The sensor has two outputs, one for the ECU and one for the dash.
VAG-COM readout:
[16502 - Engine Coolant Temp. Sensor (G62): Signal too High
P0118 - 000 - - - Intermittent]
***
Tools needed: hands, left and right (nitrile gloves are handy) and some rags.
Verify the replacement part.
Done on my 04 Bora from the top only!
Steps
1) Engine should be cold before you begin.
2) Open hood. Where the yellow arrow is pointing to, is where we are going.
[FONT="]
[/FONT] Moving closer, you can see the glow plugs for the coolant where the yellow arrow is pointing. Underneath there we go.
[FONT="]
[/FONT] Here is a better side shot of what you will be seeing when doing the repair. If you look down where the yellow arrow is pointing you will see what is on the next picture.
[FONT="]
[/FONT] Here is our target. The yellow arrow is pointing to the plastic clip and the blue arrow is pointing to the plug.
[FONT="]
[/FONT] I dropped the camera underneath and took ~20 shots till I got this one.
[FONT="]
[/FONT] Now you know where it is the real fun begins.
3) Place your new sensor with the O-ring already seated on it where you can quickly get it. Make sure it is not on a surface where it can roll away. The spare plastic clip should be next to it as well.
4) Remove your watch and reaching with your right hand route your hand down the side to underneath the sensor and gently pull the plastic clip downwards. There is a very good chance you can do this without breaking it. (See yellow arrow in above picture)
The next few steps are to be done in quick succession:
5) Wiggle the plug so you know it will come out.
6) Ready the new sensor (with O-ring already seated) in left hand.
7) Get into a position where you can see the plug.
8) Pull the plug out! (Coolant will now pour out. This is expected)
9) Verify that the old O-ring is out by touch or visually and if not drop the old sensor and go pull the old O-ring out with your finger. (Don’t worry the old sensor is still connected to the plug. It won’t go far)
10) Left hand brings to the right hand the new sensor and the right hand seats it back into place. (Don’t toss anything here. The last thing you need is to see your new sensor fall through your right hand’s fingers)
Once that is done you can slow down.
11) Firmly press the new sensor into its’ place and return the plastic clip.
12) Remove the plug from the old sensor.
13) Orient and place the plug onto the newly installed sensor.
This is a blurry picture of where the right hand was during the procedure.
14) Top up any coolant as needed and clean up.
15) Test your work.
I don’t have VAG-COM so the CEL was still there that night but the next morning it was gone.
This took me 15 minutes to do. I’m not mechanically inclined but I did my R&D before trying.
***
I had a CEL light that was intermittent and the idle would vary from 900 to 1100 rpm. Talked with B2P and we used his VAG-COM to check the fault code. The fault code P0118 was found. The dash temperature was 90C and the ECU was seeing –4C. The sensor has two outputs, one for the ECU and one for the dash.
VAG-COM readout:
[16502 - Engine Coolant Temp. Sensor (G62): Signal too High
P0118 - 000 - - - Intermittent]
***
Tools needed: hands, left and right (nitrile gloves are handy) and some rags.
Verify the replacement part.
Done on my 04 Bora from the top only!
Steps
1) Engine should be cold before you begin.
2) Open hood. Where the yellow arrow is pointing to, is where we are going.
[FONT="]
[/FONT] Moving closer, you can see the glow plugs for the coolant where the yellow arrow is pointing. Underneath there we go.
[FONT="]
[/FONT] Here is a better side shot of what you will be seeing when doing the repair. If you look down where the yellow arrow is pointing you will see what is on the next picture.
[FONT="]
[/FONT] Here is our target. The yellow arrow is pointing to the plastic clip and the blue arrow is pointing to the plug.
[FONT="]
[/FONT] I dropped the camera underneath and took ~20 shots till I got this one.
[FONT="]
[/FONT] Now you know where it is the real fun begins.
3) Place your new sensor with the O-ring already seated on it where you can quickly get it. Make sure it is not on a surface where it can roll away. The spare plastic clip should be next to it as well.
4) Remove your watch and reaching with your right hand route your hand down the side to underneath the sensor and gently pull the plastic clip downwards. There is a very good chance you can do this without breaking it. (See yellow arrow in above picture)
The next few steps are to be done in quick succession:
5) Wiggle the plug so you know it will come out.
6) Ready the new sensor (with O-ring already seated) in left hand.
7) Get into a position where you can see the plug.
8) Pull the plug out! (Coolant will now pour out. This is expected)
9) Verify that the old O-ring is out by touch or visually and if not drop the old sensor and go pull the old O-ring out with your finger. (Don’t worry the old sensor is still connected to the plug. It won’t go far)
10) Left hand brings to the right hand the new sensor and the right hand seats it back into place. (Don’t toss anything here. The last thing you need is to see your new sensor fall through your right hand’s fingers)
Once that is done you can slow down.
11) Firmly press the new sensor into its’ place and return the plastic clip.
12) Remove the plug from the old sensor.
13) Orient and place the plug onto the newly installed sensor.
This is a blurry picture of where the right hand was during the procedure.
14) Top up any coolant as needed and clean up.
15) Test your work.
I don’t have VAG-COM so the CEL was still there that night but the next morning it was gone.
This took me 15 minutes to do. I’m not mechanically inclined but I did my R&D before trying.
-30-
