Hopefully, someone who actually performed the task them self will chime in. You probably have seen this already but just in case you didn't, it may help. 1) Originally Posted by Hackman
I had the problem of no brakes. Cleaned all the ground connections from battery to the frame. I have had no problems in the last 2 years. 1 under the battery 1 behind the front wheel and 1 on passenger side firewall.
Has anyone else tried my solution? I had the car for three years after the fix and had no issues. I think when a new hcu is installed, a secure ground connection is reestablished, that is why the replacement seems to work.

Good luck!

 

Mine is a 2008 also and I gather from the PDF that the 05-07 grounds may be in slightly different locations?.

The ground wires are on the right frame rail of the body as the PDF suggests - Top Picture. There are stud-post bolts that are attached to the rail. The HCU bracket mounts with these studs and nuts are then fastened. Then the two original ground wires are attached and another set of nuts fastened. I thought I had taken some pictures, but I cannot find them.

Problem is that both must really be done from underneath the vehicle. If you lean over the engine and look straight down under the black cylindrical body off the HCU (the pump motor), you should see the top ground wire. Might be able to finesse from above, but I doubt it. The bottom ground is about 6 inches lower and about 6 inches back towards the firewall.

I replaced the grounds with the kit I mentioned in a post above. I think it also had some teethed washers to help "bite" the metal on the washers and nuts.

If you don't have a way to do it yourself, I think you could take it to about any garage with a lift and a mechanic should be able to see and clean them. It shouldn't take more than an hour shop time in my opinion.

Good Luck!

 

This shows the entire HCU mounting. The ground wires are items 13. I thought the studs were mounted in the rail, but they are actually bolts with another threaded extension to accept the ground wires.

 

Thanks for all the replies on the grounds!!!

My 2008 (126K) has been making the HCU noise periodically (including one 'check brake system' notice) over the past few months (I had the rear pads replaced at a Ford Quicklane in December), and I am considering a flush/bleed as a preventative measure. So is a bleed/flush something that should be done after brake pad replacement? Also, does this have to be done at a dealership as the manual implies?

Thanks!

 

If the hydraulic brake system was not "opened" to allow any air in, I wouldn't think you would need to bleed the system. But if the fluid has never been changed, it's more than passed time to do it.

Doesn't have to be done by a dealership.

Lois0697's post #12 in this same thread is a "electronic" way to do it.

I have done it with a pump up pressure bleeder at around 20 PSI and the battery unhooked.

I have the Ford Service manual for the 2008 year and the official procedure is a combination of their ETIS service computer with a pressure bleeder.

 

Hey LonnieU, wondering if you or anyone had experience with code 1187? I just had the ABS Lock Controller harness replaced, cleared all the other codes but popped up with 1187. One other observation, the car is going into EV mode more frequently since the change. I have no idea why, any thoughts?

Regards,
Lois

 

Lois,

From the Service Manual, this is a "Brake Fluid Level Sensor Input Open Circuit" fault. I have attached a Dropbox link to download a zip file of the pages in question at the bottom of this post. Zip file was to big to attach.

It would sound as if the installation of the wiring harness has a open connection to this fluid level switch. The switch is located inside the Master Cylinder reservoir and not individually replaceable (Got to Love it!). If you look at the last scanned page, it is the schematic of the switch to the Brake Control Module. There are resisters in parallel with the switch contacts so the BCM always gets some voltage level back.

There appears to be a plug for this switch on the side of the reservoir, C124. This could have come unplugged during the change out and would cause this code.

If you can unplug this connection and read the resistance of the switch and you should get 1200, 2700 or 4200 ohms if its working and depending on the levels detected. If all looks good there, one of the connections is not making it back to the BCM on pins 3 & 28.

The scanned pages detail the troubleshooting procedure.

Good Luck!

Scanned Pages Zip File

 

Thanks Lonnie, forwarded to my mechanic. I know there is nothing unplugged. However, I'm wondering is it possible the new harness (defective) is causing this, it's an after market part. Should I consider getting a used Ford part, Ford won't sell separate from the entire harness anymore, entire harness approx. $2000. Also, is this dangerous to drive in this condition? Everything appears to be working fine. So appreciate your assistance!

 

Lois,

I think if the ECU was not "happy" for the vehicle to drive, you would get the "Stop Safely Now".

The DTC Code is reporting a failure of the Reservoir Level Switch, not that it's Full or Empty. So long as it's full !!

The SSN above should go active on loss of main brake pressure if it was low or empty...

I would have your mechanic should see if they can find the Blue/Brown wire and the Green wire in the harness as shown on the schematic. Then follow the troubleshooting procedure. It could just be a bent pin that didn't make up on the plug/socket connection. Only after that would you might want to go looking for a used OEM part.

IIRC, all the models up to 2008 used the same/similar wiring harness. 2009 and after went back to a "conventional" brake system and the HCU unit is gone. It has an electric pump to provide a Vacuum since there are time the ICE won't be running. I looked for a 2009 and above AWD in my area before I got my 2008. Should have looked harder

Again, Good Luck!

 

That made me laugh! Granted, had I known then what I know now, I would have went for 2012 non hybrid but I haven't lost hope...yet. In regards to brake fluid level, it is full and I have no problem doing a manual check if that was the only possible hiccup. These cars have so many twists and turns, I wanted to hear it from someone more knowledgeable than I am. So appreciate your prompt response and wisdom.