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2014 Jeep Grand Cherokee Summit V8 "Service Electronic Brake System"

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8.5K views 18 replies 3 participants last post by  HookedonJeep  
#1 ·
Yesterday, I was backing out of my garage and I heard what it sounded like a hydraulic gas release. In addition sometimes the vehicle has a hard time starting and I have a fully charged battery. I have almost 90k miles and this morning when I pushed the start button it wouldn't turn over and I got a warning on my cluster gauge it read "Service Electronic Brake System" and it started fine on the second try. However, this is the second time it has done this within the last 3 months and I am a bit concerned. I am not sure if the what it sounds like a hydraulic gas release once in a while (I've heard it twice as I was backing out of my garage so far) and I tried to pull codes but nothing came up. TIA!
 
#2 ·
The gas release may be the air suspension working, or a leak.

You would need a OBD scanner that can read body codes, like AlfaOBD or Appcar, so see errors in all modules other then the PCM. Some inexpensive scanners can read ABS and Airbag faults.

A bad brake switch can cause intermittent no starts and brake fault messages. Its a three contact switch in the brake pedal assembly. Its fairly easy to replace, there is a thread around here somewhere with instructions. You may want to just replace it and see how it goes.
 
#4 ·
Easier for me to repost than search :). If yours is like early models, it should be:

1.Disconnect and isolate the battery negative cable.

2.Remove the steering column opening cover from the instrument panel.

3.Depress and hold the brake pedal in the depressed position.

4.Rotate the brake lamp switch housing (2) counterclockwise about 30 degrees to align the switch locking collar with the keyed square hole in the brake pedal mounting bracket (1).

5.Pull the switch straight rearward from the keyed hole to remove it from the bracket.

6.Release the brake pedal.

7.Disconnect the body wire harness connector (3) from the brake lamp switch.
 

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#5 ·
Dunno off hand if the brake booster recall is applicable to your year, but they can rust out over time and leak. The gas release type sound could be a leak in the booster, which could also be a vacuum leak that makes for hard starting and poor performance. That could also set the warning message.

Just guessing here, reading the ABS module codes may be helpful.
 
#7 ·
I turned on all the notifications but no warning or error codes. My two ODBII readers don't have anything with ABS on them and I have been pushing the button without applying the breaks and leaving it on run for a few second before starting the vehicle and that seems to work for now. However, I am still hearing this puff noise from the back as if I am in a semi truck which I never heard before or never noticed it before. Any ideas as to what that hydraulic puff might be? How concerned should I be? I emailed the dealer today to see what services are coming up since, I have 90k now and the last time I was there I was told to replace the transmission fluid? Of all the years I have owned vehicles I've never had to replace transmission fluid in my vehicles. What are your thoughts on replacing the transmission fluid?
 
#11 ·
I I have 90k now and the last time I was there I was told to replace the transmission fluid? Of all the years I have owned vehicles I've never had to replace transmission fluid in my vehicles. What are your thoughts on replacing the transmission fluid?
The ZF transmission fluid is supposed to be "lifetime" under non-severe use which is why there's no dipstick, but the definition of "lifetime" can be subjective. Approaching 100K, I would be leaning towards having it checked and/or serviced.
 
#8 ·
Turning the ignition on without applying the brakes allows time for the fuel pump to spin up an build pressure. If it starts routinely using that procedure, thats a symptom of a bad pump or a bad pump relay, or another fuel problem.

You may want to check fuel pressure and leak down.

Wonder if the evap system is being over pressurized, or over vacuumed and a relief or check valve is releasing the pressure. Dunno, but its a story :smile2: If you are sure its coming from the rear, the only things back there are air suspension, fuel delivery, and emission system components. All can make unusual noises.
 
#9 ·
Turning the ignition on without applying the brakes allows time for the fuel pump to spin up an build pressure. If it starts routinely using that procedure, thats a symptom of a bad pump or a bad pump relay, or another fuel problem.

You may want to check fuel pressure and leak down.

Wonder if the evap system is being over pressurized, or over vacuumed and a relief or check valve is releasing the pressure. Dunno, but its a story :smile2: If you are sure its coming from the rear, the only things back there are air suspension, fuel delivery, and emission system components. All can make unusual noises.
it's definitely a hydraulic pressure sound. It sounds like a semi truck and I just read through the entire owner's manual and I guess I don't have a diagnostics option on the evic for the suspension system.
 
#10 ·
No you need a full featured OBD scanner like AlfaOBD or AppCar to run diagnostics or view status.

There is a compressed nitrogen (air) tank behind the rear seat under the cargo floor. I often hear a ping type noise as the suspension adjusts. What happens when you raise and lower the suspension, hear any semi truck noises?
 
#12 ·
Ok, I just got a message on my cluster this morning while I was driving "Service Air Suspension System Immediately" so, I think the gas leak I've been hearing from the rear is related to this. I have called the dealership and they can't get me in until mid next month. How worried should I be? Can I just put it in tire jack mode to disable air suspension and drive it until I get it resolved?
 
#13 ·
Jack mode automatically disables when you drive over 5mph or so. You may be able to pull the compressor fuse, or the connector off of it. You do not want it to let it drop so much you bounce off the suspension stops as that starts to ruin things pretty quick. How often are you getting the service air suspension message?
 
#15 ·
Should be in the owners manual, F05 I think on a 2014, but double check.

Gas is always moving in and out of the tank. You need to be listening for the air compressor, which is passenger side front. If it is running a lot there is a leak.

I wouldn't worry too much about it until you get a second message, unless you are hearing a lot of compressor... its not meant for continuous duty.

If the compressor isn't running and there is a leak, the ride height will eventually drop. You don't want to be dropping to park level and driving on it. Dunno what to tell you besides look at a loaner.
 
#16 ·
Should be in the owners manual, F05 I think on a 2014, but double check.

Gas is always moving in and out of the tank. You need to be listening for the air compressor, which is passenger side front. If it is running a lot there is a leak.

I wouldn't worry too much about it until you get a second message, unless you are hearing a lot of compressor... its not meant for continuous duty.

If the compressor isn't running and there is a leak, the ride height will eventually drop. You don't want to be dropping to park level and driving on it. Dunno what to tell you besides look at a loaner.
it sounds as if the sound is coming from the tank in the back. However, I had the tire jack mode on last night and when I woke up this morning it looked as if the front side was low. As soon as I took it off the tire jack mode off it leveled itself. I was going to get an odbII scanner with abs but I guess those don't scan codes for the suspension system and the ones that do are very expensive. I am not sure how else I can find what the issue is but take it to the dealer to be honest. I wiggled the two front lines by the engine compartment yesterday and I didn't hear any air coming through them. When I am sitting in my car the tank in the back makes a semi truck puff noise. And that's what started all this to begin with it would just make a semi truck hydraulic gas release noise.
 
#17 ·
Without the codes, you are pretty much dead in the water except for checking for leaks. The puff you hear it the suspension system making adjustments.

You need a full featured OBD scanner to read the suspension system codes, like AlfaOBD or AppCar.

You should spray/brush soapy water on fittings and hoses to check for leaks, similar to finding a nail in a tire.
 
#18 ·
Without the codes, you are pretty much dead in the water except for checking for leaks. You need a full featured OBD scanner to read the suspension system codes, like AlfaOBD or AppCar. On the other hand, the scanners is not going to help much with leaks other to show the compressor is overheating. If the scanner can also send commands, you may be able to calculate the state of fill. From your description, it seems pretty clear its probably a leak. Once you fix it, you will need to return to the dealer for purge and refill.

You should spray/brush soapy water on fittings and hoses to check for leaks, similar to finding a nail in a tire.

The puff you hear is the suspension system making adjustments by opening and closing one valve or another. Its normal for those with exceptional hearing to hear the air moving, sometimes the valves ping.