2003 MKIV Wagon Rear Door Hatch won't respond to fob

Hey folks--here's an issue that has been a point of consternation for me for the past few months since I picked up this car. My previous diesel (97 B4V) didn't have a remote so I never had to fool with it, but this one does. I've replaced the door latch actuators on the front driver and passenger sides and they are working fine, as well as replacing the CCM comfort control module under the dash. The last few electrical things I have to address are the rear door not responding to the fob and the occasional ghost opening and closing the sunroof.

The hatch control switch in the passenger door works ok--it previously had issues but I just replaced it a few days ago. The original switch was definitely broken.

The key works fine when turned in the back door. You open the door, get your stuff out and shut it and the horn honks and the rear lights flash to tell you the system is armed.

The side doors respond to the fob, both to lock and to unlock.

I took the fob to a key shop and the person there tested it said there wasn't an issue with it.

I took the back door cover off and had a look around and all the plastic and metal parts seem intact and relatively clean.

I took off the door latch mechanism and cleaned it (didn't take it fully apart, though) and reinstalled it. This didn't change anything.

I checked the wiring harness entry points for broken wires and didn't find any.

When I put the keys in the ignition and the rear hatch is open I get a "door is open" light on the dash.

Local shop suggests getting a new hatch latch mechanism.

Is there anything else I ought to look for before buying one of these?

Thanks,

David Dillard
Louisville

What does the CCM say when you press the hatch button on the fob? That data will at least let you know that the signal is being received.

The open actuator works from the door button so I can't see it being a wire problem.
The CCM control's it.
Did you scan for codes?
Was it a new CCM you installed?
Not sure if a new CCM has to be programed or not but your door's unlock from the fob.
Was it made in China?

Another thought.
Measure the voltage at the motor that unlocks it while the fob is held for 3 seconds, and if the door unlock button is pressed.
Its a blue wire in mine.

Thanks for the help. I don't have the technology to scan for codes or read the CCM. The CCM is new OEM, but there is a chance it wasn't programmed correctly for the rear hatch.

As far as regards code reading, is this the kind of situation where I can go to an Autozone and have it done?

Is the CCM the place where fob signal is interpreted?

I'll check the voltage at the unlock motor.

Thanks again!

How could you install a new CCM without a scan tool????

I didn't install it myself--I had a local shop do it. Just not sure if they programmed it right or if there's something else to fix. Sorry for the lack of clarity.

OK, well you are going to need a scan tool to get very far here. You also need to know it was coded correctly, as well as if the CCM was the same part number or not.

The CCM was a match. And I agree I need to get a scan tool.

VCDS Lite works on a Windows laptop if you have a OBD cable that's compatible with it.
The free version does most of what you need to test it.
I registered it for $99.00 (US) and everything I need works.

If you hold the button the hatch unlocks? On mine it just turns off the alarm so I can use the key. I hear something actuate but it's still locked until I use the key. I did find a screw rattling around in there.

Bump to the top, same problem. Just bought and programmed a key from Tunemyeuro. The key for opens the doors but not the rear hatch of my wagon, mk4, 2003 Jetta, default royal blue. Help please.

Is there a red LED on the fob? Does it flash when you press the hatch release button?

Does the door switch operate the hatch?

If no, you are looking for an issue with the latch actuator or wiring to it, possibly at the flex point between the hatch and body.

If yes, you need a scan tool to determine if the CCM sees the signal from the fob.

My problem was identical to the op's. I had to SUSTAIN THE BUTTON for a full second for the hatch to unlock.

Cosmo's UNA said:

My problem was identical to the op's. I had to SUSTAIN THE BUTTON for a full second for the hatch to unlock.

Click to expand...

By design. Sedan trunk works the same way.