TCU Module power drain affects power steering

[gonedawning]

Hi everyone,

Bad day today - Ford dealership told me they could not repair my 2013 C-max hybrid TCU module and power steering issues. Ford tells me that the TCU module has been draining the power system which has now compromised the power steering and that a replacement TCU module is not sold through Ford anymore and would be difficult to find. Problems started last year and then went away after a dealership returned the car (couldn't find the part?). Car ran great for a year and then the same issues started up again. Now a new dealership is telling me the same thing!  That's after a $250 diagnostic and repair quote for $4,200 to fix! Am I alone here? Can the car be repaired? Any thoughts to cheer me up a bit?

[cr08]

Sounds like the dealer is throwing you a lot of BS. I can't see how the TCU having an increased power drain (it can't really drain that much on its own without going up in a literal ball of flames) would cause the power steering system to fail.

 

Unfortunately while not overly common, there have been a good number of cases of the power steering failing on Ford vehicles around this MY/build timeframe. Usually comes down to an internal failure of the assist motor and electronics due to poor solder joints. The fix is to replace the entire steering rack. $4200 seems a bit much for that though. My vague recollection tells me others have been quoted around the $2-2.5k mark.

 

At this point, I'd highly recommend trying other dealers as it sounds like this one is just trying to take you for a ride.

[jzchen]

Can you please be more specific as to the "power steering issues" you are dealing with?

[gonedawning]

On 10/5/2022 at 12:27 PM, jzchen said:

Can you please be more specific as to the "power steering issues" you are dealing with?

Sure and thanks to everyone!!! 

Good to know about the power steering issue CR08 - thx!

 

The power steering has to be related to the TCU module if only because the radio won't turn off or the sync dies or bluetooth dies...strangely coincidental.

First it's the communications, then the auto assist for the steering starts getting sluggish just when the car starts - after about 30 seconds it kicks in.

After about two weeks of daily driving, the auto assist steering delays more and more, then the car dies altogether.

Even AAA tells me there's 0 zero charge on the battery.  Both my batteries (12v) are brand new so it's not a battery issue. The dealer who has the car confirmed that the fuses are ok and the batteries are okay.   Thinking that the TCU module is messy up power management. 

 

Another question... is the car driveable without the TCU module?

[gonedawning]

On 10/5/2022 at 12:27 PM, jzchen said:

Can you please be more specific as to the "power steering issues" you are dealing with?

On another note - there are no noises, leaks or tactile feedback from the steering - smooth as silk.

[cr08]

The vehicle is drivable without the TCU, but you will lose out on the Value Charge and Go Times features if you use those as they are operated on the TCU itself.

 

I'm still doubtful the TCU is a cause but more of a symptom. There have been no anecdotes on the number of C-Max or Fusion communities that I follow indicating issues with the TCU causing undue battery drain or killing other modules.

 

-How- new is the 12v battery? You also say Sync has had issues where it won't turn off or it dies. It's a VERY common issue on these older models with Sync 2 for there to be a battery drain by the ACM failing to turn off at key-off. This has been WELL documented. Depending on how often this happens, it could be the cause of your issues especially if you let the vehicle sit in this condition and drain the battery. I'd love to have more details on this, ie: Do you get any weird error messages or displays on the touch screen? How often do these radio/infotainment related symptoms happen?

 

Your comment about it taking the power steering about 30 seconds to kick in after starting: My -educated- guess is it is seeing the low battery voltage and waiting for it to come back up after the vehicle is started before it activates. I'll look through my workshop manual to see if it confirms behavior like this.

 

If you have the option to test, may be worth putting the vehicle on a trickle charger while it is sitting and see how it behaves then. If the power steering is fine afterwards and doesn't have the delay, it's probably something along the lines above and probably doesn't need the power steering rack replaced as your dealer is trying to push you toward. Are there any other power steering specific symptoms other than the delay on startup?

 

EDIT: Here's an excerpt from Ford's workshop manual:

 

Quote

Failure Modes

When a DTC is present in the PSCM , the EPAS enters 1 of 2 modes of operation.

The EPAS enters a reduced steering assist mode to protect the internal components of the EPAS when a concern is detected by the PSCM such as low/high battery voltage or over-temperature concerns that are not considered to be a critical safety concern. This reduced steering assist mode gives the steering a heavier than normal feel.

The EPAS enters a manual steering mode (no electrical steering assistance is provided) when a concern that is considered to be a critical safety concern is detected. In manual steering mode, the vehicle has mechanical steering operation only, which gives steering operation a heavy feel.

 

One note: The second failure mode mentioned in the above excerpt will usually give a clear warning about needing the power steering system serviced. If you haven't gotten a message like this, even more of a reason to doubt outright failure JUST yet.

Edited October 6, 2022 by cr08

[nogoodbum]

To expand on cr08's questions about the 12v battery status, I'd point out a few things. When a dealer [not just Ford but all major brands], is authorized to sell a model, they are required by guidelines to have on hand a certain amount of regular parts for upkeep of that model [filters, brake pads, batteries etc.] & the manuals & tools required. In some cases this means a large investment on the side of the dealer. If you notice often the dealer will portray signs that are certified repair centers for different models of the same car [especially high performance models], which basically just means they have made the investment, [not that they repair these models on a regular basis]. Some of these parts [as in the case of the C-Max battery]  can sit of a shelf for years until needed because of the low #s of cars sold that need the part. Unlike filters, pads, & etc, batteries decay as they sit & wait. I went thru a like runaround with the local dealer here [car was in shop for 3 months during a 6 month period] until they finally admitted the "new" battery they sold & installed was bad. Some dealers just don't want to admit errors & faulty parts for some reason. If you can, check the date of manufacture of the 12v battery [not the date of sale or installation], & have the battery load-tested by an outside party. Thanks for the read

[gonedawning]

On 10/6/2022 at 3:23 PM, cr08 said:

The vehicle is drivable without the TCU, but you will lose out on the Value Charge and Go Times features if you use those as they are operated on the TCU itself.

 

I'm still doubtful the TCU is a cause but more of a symptom. There have been no anecdotes on the number of C-Max or Fusion communities that I follow indicating issues with the TCU causing undue battery drain or killing other modules.

 

-How- new is the 12v battery? You also say Sync has had issues where it won't turn off or it dies. It's a VERY common issue on these older models with Sync 2 for there to be a battery drain by the ACM failing to turn off at key-off. This has been WELL documented. Depending on how often this happens, it could be the cause of your issues especially if you let the vehicle sit in this condition and drain the battery. I'd love to have more details on this, ie: Do you get any weird error messages or displays on the touch screen? How often do these radio/infotainment related symptoms happen?

 

Your comment about it taking the power steering about 30 seconds to kick in after starting: My -educated- guess is it is seeing the low battery voltage and waiting for it to come back up after the vehicle is started before it activates. I'll look through my workshop manual to see if it confirms behavior like this.

 

If you have the option to test, may be worth putting the vehicle on a trickle charger while it is sitting and see how it behaves then. If the power steering is fine afterwards and doesn't have the delay, it's probably something along the lines above and probably doesn't need the power steering rack replaced as your dealer is trying to push you toward. Are there any other power steering specific symptoms other than the delay on startup?

 

EDIT: Here's an excerpt from Ford's workshop manual:

 

 

One note: The second failure mode mentioned in the above excerpt will usually give a clear warning about needing the power steering system serviced. If you haven't gotten a message like this, even more of a reason to doubt outright failure JUST yet.

On 10/5/2022 at 12:27 PM, jzchen said:

Can you please be more specific as to the "power steering issues" you are dealing with?

On another note - there are no noises, leaks or tactile feedback from the steering - smooth as silk.

 

On 10/6/2022 at 3:23 PM, cr08 said:

The vehicle is drivable without the TCU, but you will lose out on the Value Charge and Go Times features if you use those as they are operated on the TCU itself.

 

I'm still doubtful the TCU is a cause but more of a symptom. There have been no anecdotes on the number of C-Max or Fusion communities that I follow indicating issues with the TCU causing undue battery drain or killing other modules.

 

-How- new is the 12v battery? You also say Sync has had issues where it won't turn off or it dies. It's a VERY common issue on these older models with Sync 2 for there to be a battery drain by the ACM failing to turn off at key-off. This has been WELL documented. Depending on how often this happens, it could be the cause of your issues especially if you let the vehicle sit in this condition and drain the battery. I'd love to have more details on this, ie: Do you get any weird error messages or displays on the touch screen? How often do these radio/infotainment related symptoms happen?

 

Your comment about it taking the power steering about 30 seconds to kick in after starting: My -educated- guess is it is seeing the low battery voltage and waiting for it to come back up after the vehicle is started before it activates. I'll look through my workshop manual to see if it confirms behavior like this.

 

If you have the option to test, may be worth putting the vehicle on a trickle charger while it is sitting and see how it behaves then. If the power steering is fine afterwards and doesn't have the delay, it's probably something along the lines above and probably doesn't need the power steering rack replaced as your dealer is trying to push you toward. Are there any other power steering specific symptoms other than the delay on startup?

 

EDIT: Here's an excerpt from Ford's workshop manual:

 

 

One note: The second failure mode mentioned in the above excerpt will usually give a clear warning about needing the power steering system serviced. If you haven't gotten a message like this, even more of a reason to doubt outright failure JUST yet.

CR08 - you are a gem!!!

Don't need the TCU module - but now I am suspicious that this may not be the underlying problem. The dealership has told me they "cannot find" a replacement part so can't repair.  Having them remove and reserve and may replace later.

 

I do work from home and during COVID put few miles on the car (2020 - 2021).  The fact that the car drains so quickly does support your ACM theory. Once jumped and driving the battery gage and functionality of the car appears to be quickly restored - it's after I turn off the car that strange things happen overnight (haunted car!).  Typically, I never get any error messages or warning lights - even the sluggish power steering is not warned. Only two warnings have lit in the nine years of ownership 1) the power steering warning - but only when the steering is FULLY manual - it does NOT come on during the times that the power steering assist is sluggish and then kicks in after 30 secs. 2) and one time I tried to start the car and every single light, warning, message, horn ...flashed before me - I was terrified! and then - dead car, like a last gasp of life before death! (I actually have a picture of the flashing dashboard I can post.) This was the morning after the installation of the brand new battery by the original dealer! The dealer returned the car after new battery install, I drove the car home with no problems, parked the car in the garage - then the next morning - BOOM dead car!

 

The touch screen did have an error messages once - when time the radio would not turn off - the touch screen did not work/respond. This SYNC issue was related to the latest power management and power steering loss too.

 

Don't have options to test the power system myself - you would have to walk me through.... sorry....

 

Specifics on the delay to power steering. There are been two occasions, both have identical symptoms. The related radio and SYNC issue is starred** this happened on the second occasion.

#1) I first note that the steering wheel is a bit stiff on starts for about 10 seconds - this condition lasts about 20-30 car starts and does not consistently occur at every start

#2) then the PS becomes sluggish on starts and continues through driving for about 10-30 seconds (5 meters) then PS kicks in and the car is fine - this condition lasts about 10 car starts and occurs consistently at every start**

**#3) then PS never kicks in after driving - the PS warning light appears. I drive home and park the car (whew!) and call the ford dealership for service.

#4) Cannot start the car. All power is lost. A jump is needed to start the car. After jumping, the car drives fine.**

[gonedawning]

On 10/7/2022 at 2:58 AM, nogoodbum said:

To expand on cr08's questions about the 12v battery status, I'd point out a few things. When a dealer [not just Ford but all major brands], is authorized to sell a model, they are required by guidelines to have on hand a certain amount of regular parts for upkeep of that model [filters, brake pads, batteries etc.] & the manuals & tools required. In some cases this means a large investment on the side of the dealer. If you notice often the dealer will portray signs that are certified repair centers for different models of the same car [especially high performance models], which basically just means they have made the investment, [not that they repair these models on a regular basis]. Some of these parts [as in the case of the C-Max battery]  can sit of a shelf for years until needed because of the low #s of cars sold that need the part. Unlike filters, pads, & etc, batteries decay as they sit & wait. I went thru a like runaround with the local dealer here [car was in shop for 3 months during a 6 month period] until they finally admitted the "new" battery they sold & installed was bad. Some dealers just don't want to admit errors & faulty parts for some reason. If you can, check the date of manufacture of the 12v battery [not the date of sale or installation], & have the battery load-tested by an outside party. Thanks for the read

NoGooDbUM - thanks so much for your feedback!!!

The first and original dealership refused service when I returned with the same problem presented a year ago (1st: 3/24/2021 - 88775 miles and 2nd: 9/15/2022 - 95532 miles). So, my car is currently at second ford dealership. And they are not keen on returning my car. I brought the car in a week ago and they ran the diagnostic and provided a quote for the Power Steering Module and the TCU replacement. I'm in a stalemate since they can't find a TCU module replacement and have yet to revise my quote for the power steering. I think ford is really struggling. (ford motor company customer service is quite rude and putoffish - so sad really)

All I can do is ask the dealer to check the battery manu. date. Load test can be done by AAA.

Incidentally, when I bought the car in 2013, the 12v battery died within 12 months, probably for the reasons you've describe. 

Not sure why Ford can't find a replacement TCU module - seems odd....

[cr08]

On 10/7/2022 at 4:18 PM, gonedawning said:

Not sure why Ford can't find a replacement TCU module - seems odd....

 

Right now they are no longer replacing with the old 3G TCU's and have to replace it with a 4G model per Ford's directives. Unfortunately for the C-Max they have had some issues and part of the 4G upgrade program they have held off upgrades until new TCU parts are in. But they state it should be available Q4 2022 meaning right now up until end of year. Unfortunately I don't have any specific 'inside baseball' on the current status of that.

 

It may not hurt either to have the dealer check and run some of the battery drain related TSBs especially if you are first owner of this 2013 and never had any of them applied. These early models had a number of power and battery drain issues early on that were largely fixed with software updates. I'll see if I can track down specific TSBs if someone else doesn't chime in with them.

[SnowStorm]

If it hasn't been done (I doubt it), see if your dealer can perform CSP 15B04 - read it here.  It seemed to clear up dead 12v battery problems for a lot of us years back.

 

It does sound like you may be having overnight 12V battery drain issues.  A good (or new!) battery can be drained beyond full discharge (below 10.5 volts) when the problem occurs.  I once saw mine down around 4 volts!  You can charge it back up and it may load test OK but keep doing it and the battery is progressively degraded.  What happens when you try and start the car depends on how low it went.  If it only went down to maybe 8 volts (?) it might still start with you unaware of what happened.  Or you might have some errors.  At some point the car won't start and has to be jumped.  You might get a cheap voltmeter and plug it in the 12v jack in the back (it doesn't turn off).  Check it often and see what is going on.

[gonedawning]

Thanks SnowStorm!!!

All things are pointing to the battery. Loved the link! (Although broken) Found so much more information.

[SnowStorm]

What happens when you try the link?  It still seems to work for me.  It should go to:

   https://ford.oemdtc.com/1696/15b04-12-volt-battery-test-and-module-software-update-2013-2014-ford-c-max

 

 

[jestevens]

Yeah, sure sounds like the old 12V battery drain issues to me. Lately I've noticed my car won't unlock again, I have to open the door with the key inside the fob and then start it up with the FOB next to the steering column once inside.

Ever since COVID they have been letting us work remotely more. I don't drive it on a daily commute and the 12V is probably going low from lack of routine charging. I left the car "idle" in the mall parking lot with the climate control off yesterday for about an hour while I was getting an eye exam. Just locked the door with the FOB. That seems to have been enough to restore normal operation for now.

If the 12V goes bad too many times I suppose it could actually damage the battery. For the Prius I bought one of those gold top optima AGM batteries so that way if it went completely dead I could still charge it -- although I never had parasitic drain with that car.

I didn't typically didn't have issues with the 2013 C-MAX SEL either, but a handful of times as it's gotten older I've had to pull the fuse when the touchscreen became non-responsive and the amp wouldn't output any sound. Now I keep a small toolset with pair of piers and a tire plug kit in the back of the car at all times. Edited November 11, 2022 by jestevens