348 AC error code E5

Have you done this yet? http://ferrarichat.com/forum/showthread.php?t=19629

Or how about this one? http://www.ferrariforum.com/tech/view.php?id=14

If not give those a try.

Here is a diagram of the system.
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You have to remove the trunk liner.

Remove the rubber seal around the top of the liner.

Then remove the screws hold the metal trim in place.

Now lift out the liner.

 

Yes, take out the liner.

 

I haven't had that stupid liner in my car for 2 years. I run all day long with it removed. You need to be a little careful in the rain (opening the trunk), but it makes things SOOOO much easier to access.

 

I'll have a look at mine to see if I can figure something out.

 

Okay I just disconnected mine.

What you have to do is push off the little metal clip. If you turn it over you will see were the ends of the clip are open. Using a standard (flat) screw driver push one of the ends off, then take the clip all the way off. Once the clip is off it unplugs easy.

 

Mike;

Let's back up and take a slightly different approach to this, starting at the beginning. You are getting code readout of "E5" on your climate control panel. According to the manual, E5 is the code for "Motor for Heater Valve Control", which is indeed item #8 on the diagram that Ernie posted.

What is the purpose of this item? It is an electric servo motor which opens and closes a valve which controls the amount of heated coolant flowing through the heater core. Inside that motor is a potentiometer which reads the position of the lever that controls the valve. Presumably (I'm just working on theory here, not practice), a fault code is flashed if the potentiometer has readings outside its normal parameters.

What would cause such a fault? Perhaps the voltage supply is unstable, or the motor is burned out, or the valve is stuck, or the ground is faulty....who knows at this point?

If I were working on this problem, here are the steps I would take:

1) I would check the condition of the A/C system fuse and its holder, on the passenger side of the heater box. This fuse is a notorious trouble area, and is the subject of the tech tip in one of the links in the second post in this thread. If there is evidence that the fuse/holder has been overheating, install the upgraded fuse holder.

2) I would check the operation of the heater valve itself. I've posted a picture that I just took out in the garage, showing the heater control valve motor, with a pencil (not my famous "pool cue"!) pointing at the control lever on the valve. If the motor and the valve are working correctly, you should be able to see the lever move between its stops as you adjust the temperature setting on the climate control ECU. If the lever does NOT move as you adjust the temp setting, then you know there's a problem in there somewhere, not just a "ghost".

3) I would check, and clean if necessary, the electrical plug on the top of the motor, as shown in the picture. Please note at this point that the connector shown in your third picture has nothing to do with the climate control system (that's part of the anti-lock brake system).

This should give you a few things to check, in order to attempt to narrow down the source of your problem.

Keep us posted!

Edit: You asked about the ground points. You don't have to remove the dash, just the outer dash vents. The main "common ground" is accessable behind the left dash vent, a single ground wire for the A/C system is behind the right dash vent. There is a "cluster" connector on the right side of the heater box, but it ISN'T a common ground, although it looks like one.
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Awe cummon now. You got this far so why not finish the job? You've already done the hard part, and the was finding the problem. Now all you have to do is replace the part.

"YOU CAN DO IT!"

 

I just tried an experiment on my 348. The car is cold, it hasn't been run since last week. The valve is kind of in a half-way postiton, as shown in my picture. I turned on the ignition, turned on the heater, and adjusted the temp reading a few degrees. Nothing happened. The valve didn't move. I adjusted it a few more degrees. Nothing. I turned it all the way down, to "LO", and the valve shut all the way. I turned the temp up a bit, and the valve opened. So I know my servo motor and valve are working, but they didn't START working until I turned the temp all the way down.

The wire plug connector on the top of the servo motor has 5 wires. The red and white wire is the power source to the servo motor, with power coming directly from the climate control ECU (pin 16). The motor grounds through the yellow/black wire, also through the ECU. The other three wires are for the potentiometer.

I pulled the connector off the motor and hooked up a test light to the red/white wire. When I changed the temperature settings, the light comes on, which means I'm getting power to the motor through that wire (confirmed by the wiring diagram).

It's still possible that you are not getting power to the motor, in which case the problem is most likely in the ECU. I wouldn't just put a new motor into it until I confirmed that it's getting power but still not cycling. Personally, if it looked like the motor was the culprit, I would try to fix it. I hate to think what a new one would cost.

 

If you tilt the vent upwards, like you were aiming the air at the roof, you can barely see a tab on top. Depress the tab, jiggle the vent around, and off it comes. Warning - it might be a sticky MESS, if no one has stripped it!

I'll post a picture here of the common ground behind the vent. It's easier to reach if you pull the instrument panel, which is easy. That's one common ground. There is another one behind the fuse panel in the right footwell, and a single ground wire for the A/C behind the right dash vent.

The dealer can plug in a tester and run a program that will identify faults in the system. Of course it's nice if you can fix it yourself, but it's very complex, and you don't want to break something by messing with it.

Forcing the lever on the heater valve COULD cause a problem with the internal mechanism. I've never had one apart, so I don't know exactly how it works, but there is probably a gear system connecting the motor with the lever. Hopefully you can move it manually without damaging it.
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Hi Mike,

I had exactly the same problem in my car, but it is very intermittent (hasn't occurred for three-four months now) which suggests its an electrical connection problem rather than anything else.

Let me know if you do the SD1 test and what it finds out. Good luck!

Jonathan

 

Mike, could you do me a favor? You have a right to INSIST that the old part be returned to you. If you don't want it, could you send it to me? I'd be happy to pay your shipping costs on it, and I'd be interested to have a chance to take one apart and see how it works. What do you think?

Sorry it turned out not to be an easy fix.

 

I would appreciate that favor, Mike.

Don't let them tell you that they "pitched it". Call them ASAP, leave a phone message at midnight if necessary, but let them know that you expect to have the old part returned to you, intact. It belongs to you unless they installed a rebuilt part with a core charge (no chance). Personally, I would want the old part returned in the box that the new part came in, just to be sure that they actually did what you're paying for. Yes, I've been burned on this kind of thing before, being charged for parts that were not really replaced. I now ALWAYS request that my old parts be returned to me, other than things like gaskets.

Edit: You certainly don't have to say or imply that you don't trust them! Just tell them that you promised to send the old part to someone who is interested in examining it.

 

That would be *great* to see how it's set up to work. FoA has been great by me so far to date by giving me free tech support and reasonable price quotes over the phone, by the way, so I bet that they'll have the old part handy.

 

Mike; Was the dealer able to fix the E5 problem for you? Anything to report?

 

Ouch. Sorry to hear that. It's a very complex system, and I'm sure it's not a simple task to diagnose the problem. If their test apparatus told them that the valve was faulty, then that's where they would look. I'll be interested to hear what happens.