AHC - Control tube No.5 Replacement. An idiots guide from this idiot.
This is my first post here. I have had LC200 for several years and do all of my own maintenance due to the fact that UK has very little support for the 200 series, and after the insane costs of dealer service it is a no brainer to do everything yourself. After all, this is a Toyota so easy to work on.
AHC dumped all the fluid somewhere on the road in deep dark Wiltshire on my way home with the kids. AHC error on the dash and everything got very bumpy. Quick troubleshoot at home it was clear that the hydraulic line from the pump to the control block had burst (No.5 tube) due to severe corrosion (car is 2014). This is a common issue as where the heat wrap is on the pipe, right at the end of it is where the corrosion is (heat wrap removed to show the difference)
Ignore the break - this was me to aid in removal. More on this in point 5. Soak all the unions and bolts in WD40 and leave for an hour or so.
1. Pull fuse 18 in the engine bay fuse box. (50A). This will stop the pump starting.
2. Removed right rear wheel. You can see the No.5 tube union through the gap between the frame and the inner mud guard. There is NO EASY WAY to get to this union, but this is what I did. Using a 12mm ratchet spanner with a flexible neck, I removed the fixing bolt (took an hour). This allows you to lower the tube so you can get the next part done.
3. Using a crows foot and ratchet with an extension, undo the union (10mm). You may have to hold the removed pipe support with long nosed pliers whilst rotating the union. Mine was not so tight luckily.
4. Unclip the pipe from the two support along the axle and main body. No need to remove the supports but if you do a ratchet spanner is best for access (12mm).
5. Undo the hydraulic union on the left side of the underside. Cut the pipe about 150mm from the union and slide on a ratchet spanner (14mm) to disconnect the seized hydraulic union (19mm). Should have removed the rear silencer to make easier access. This union was hellish tight, and access tighter still. I removed the support bolt for the union to aid in refitting.
6. Remove the old tube.
7. WD40 the ends of the new tube as well as the ends of the two tubes you are connecting it to.
8. Slide in the new tube from left side to right side. It is a bit of a fiddle and you can bend it a little to aid in getting it through the myriad of hoses and pipes . Don't bend it too much as it will kink and then you are £140 out of pocket.
9. Connect the left side union first. In hind sight, I might of connected the right side first as it may have been easier to do point 11 but this was my choice based on ignorance. This was a real task as getting the tube and union aligned took a lot of time, and to get the union started took an hour of fiddling. Once it had bitten, an open ended 14mm and a lot of patience got it tight (very limited space with exhaust silencer in place). Bolt back up the support for the union. Do not clip in the pipe just yet.
10. This is by far the most difficult part. After lots of trials, I ended up bolting back up the union support on the left side. Then re-aligning the pipe from the pump to get the union aligned was extremely difficult through the 20mm gap! You can get your hand up in front of the frame (behind the longitudinal frame) and get your finger to spin the male union whilst your left hand is adjusting the alignment of the pipe. This took some time and trial and error, but eventually it bit. Once it was bitten I used the crows foot on an extension and once again used a lot of patience to get it fully home.
10. Clip the pipe into place in existing clamps.
11. Replace fuse (Ignition OFF).
12. Tank was empty so added 1L of fluid (£114 - 5L. Thank you Toyota!). Started car and cleared all errors several times (as pump was dry it took several attempts to get it primed as it was shut off with the error (no pump pressure). It will eventually run and start lifting the car. Get it to N height and off you go with the bleeding which has been covered elsewhere.
All in all, over 8 hours of fighting with seized unions and bracket supports, ALL of which are extremely hard to access. Good tools and patience needed with this repair.
I have made several repairs to the AHC over the years, most of it pretty straight forward. I have had faults on the accumulator as well as the damping globes, and the ride height sensors can be quite sensitive (cleaned two up to get them working again). You need techstream no question. However this repair was by far the hardest to perform even though it was a simple pipe replacement.
I hope this helps someone else who needs to do this.
Good luck.
S
This is my first post here. I have had LC200 for several years and do all of my own maintenance due to the fact that UK has very little support for the 200 series, and after the insane costs of dealer service it is a no brainer to do everything yourself. After all, this is a Toyota so easy to work on.
AHC dumped all the fluid somewhere on the road in deep dark Wiltshire on my way home with the kids. AHC error on the dash and everything got very bumpy. Quick troubleshoot at home it was clear that the hydraulic line from the pump to the control block had burst (No.5 tube) due to severe corrosion (car is 2014). This is a common issue as where the heat wrap is on the pipe, right at the end of it is where the corrosion is (heat wrap removed to show the difference)
Ignore the break - this was me to aid in removal. More on this in point 5. Soak all the unions and bolts in WD40 and leave for an hour or so.
1. Pull fuse 18 in the engine bay fuse box. (50A). This will stop the pump starting.
2. Removed right rear wheel. You can see the No.5 tube union through the gap between the frame and the inner mud guard. There is NO EASY WAY to get to this union, but this is what I did. Using a 12mm ratchet spanner with a flexible neck, I removed the fixing bolt (took an hour). This allows you to lower the tube so you can get the next part done.
3. Using a crows foot and ratchet with an extension, undo the union (10mm). You may have to hold the removed pipe support with long nosed pliers whilst rotating the union. Mine was not so tight luckily.
4. Unclip the pipe from the two support along the axle and main body. No need to remove the supports but if you do a ratchet spanner is best for access (12mm).
5. Undo the hydraulic union on the left side of the underside. Cut the pipe about 150mm from the union and slide on a ratchet spanner (14mm) to disconnect the seized hydraulic union (19mm). Should have removed the rear silencer to make easier access. This union was hellish tight, and access tighter still. I removed the support bolt for the union to aid in refitting.
6. Remove the old tube.
7. WD40 the ends of the new tube as well as the ends of the two tubes you are connecting it to.
8. Slide in the new tube from left side to right side. It is a bit of a fiddle and you can bend it a little to aid in getting it through the myriad of hoses and pipes . Don't bend it too much as it will kink and then you are £140 out of pocket.
9. Connect the left side union first. In hind sight, I might of connected the right side first as it may have been easier to do point 11 but this was my choice based on ignorance. This was a real task as getting the tube and union aligned took a lot of time, and to get the union started took an hour of fiddling. Once it had bitten, an open ended 14mm and a lot of patience got it tight (very limited space with exhaust silencer in place). Bolt back up the support for the union. Do not clip in the pipe just yet.
10. This is by far the most difficult part. After lots of trials, I ended up bolting back up the union support on the left side. Then re-aligning the pipe from the pump to get the union aligned was extremely difficult through the 20mm gap! You can get your hand up in front of the frame (behind the longitudinal frame) and get your finger to spin the male union whilst your left hand is adjusting the alignment of the pipe. This took some time and trial and error, but eventually it bit. Once it was bitten I used the crows foot on an extension and once again used a lot of patience to get it fully home.
10. Clip the pipe into place in existing clamps.
11. Replace fuse (Ignition OFF).
12. Tank was empty so added 1L of fluid (£114 - 5L. Thank you Toyota!). Started car and cleared all errors several times (as pump was dry it took several attempts to get it primed as it was shut off with the error (no pump pressure). It will eventually run and start lifting the car. Get it to N height and off you go with the bleeding which has been covered elsewhere.
All in all, over 8 hours of fighting with seized unions and bracket supports, ALL of which are extremely hard to access. Good tools and patience needed with this repair.
I have made several repairs to the AHC over the years, most of it pretty straight forward. I have had faults on the accumulator as well as the damping globes, and the ride height sensors can be quite sensitive (cleaned two up to get them working again). You need techstream no question. However this repair was by far the hardest to perform even though it was a simple pipe replacement.
I hope this helps someone else who needs to do this.
Good luck.
S
