British Engineering Axiom:

"Why use one part when seventeen will do?"

I'm posting this as a new thread to help the next person who does a search on stuck X350 glovebox latches

So... my glovebox wouldn't open (in my new to me 07 XJR). After chasing rabbits and looking in vain for a latch relay, I took things apart (glove box and passenger airbag R&R, etc) and removed the glovebox latch assembly. Its about a foot long, with latch motor dongles on each end, and a circuit board in the center. The board mounts a non removable ice cube relay (10A).

It was this $2 Omron relay giving trouble. I cut the top off, cleaned the contacts, and glued things back together. Works fine now. Made a note of the relay pn; I'll order a new one if it gives any more trouble

Hope this helps someone...

(PS: Lousy latch design. Looked up the part; looks as if Jag went to a cross shaft latch drive in later? models)

 

Good to know. What's the part number and do you have any pics of your R/R ?

 

Glovebox Latch Relay: Omron G5LC-1A4-EU (12VDC 10A)

- Remove Glovebox: 76.52.03
- Remove Pass SRS: 76.73.37

(Both procedures in Jag X350 Workshop Manual #5: Body and Paint (look in X350 forum stickies for pdf)

Note: Suggest removing SRS airbag assembly intact WITHOUT DISCONNECTING. Lay it on top of dash - the harness is plenty long

Hope this helps...

 

Thank you very much for the information. I have been battling this glove box issue for a while. It does sound like the relay is the problem, but for the life of me I cannot find where the relay is located. Can you indicate where I can find this Omron G5LC-1A4-EU on the car?

 

I will assume you have a later production model and quote relay and fuse numbers accordingly.
It is possibly the system relay R1b incorporated within the passenger junction fuse box. The schematic shows that there are two R1 relays (a and b), so it is likely there are two physical relays on the PCB rather than a combined dual relay in a single body.
Check if you have power on and through fuse F10 (5 amp) of the passenger junction fuse box. That supplies the power to the glove box motor assembly, then the front electronics module sends a command to the motor.
If no power at F10 then your R1b relay contacts likely bad.
However, if you have power at and through F10 then your problem is elsewhere. Either the fuse box motor not receiving that voltage, you have a bad motor, a bad earth to motor, or lack of command signal to motor to turn it on.

R1b being a system relay, it does not simply unplug from the fuse box assembly, therefore it is not typically user replaceable as it is soldered onto the fuse box PC board.

If you have the skills it is possible to remove the fuse box, dismantle it, then carefully separate the two PCBs, that will allow you access to desolder and replace the problematic relay and reassemble the fuse box.
Alternatively you might choose to bypass the relay by adding a suitable one in parallel with appropriate jumper wires picking up supply, earth, "relay on" signal and feeding the switched output back into correct location in fuse box.

If neither of those options are tenable for you, then you might instead be on the lookout for a replacement passenger junction fuse box.

 

Thank you very much for the information and apologizes for not specifying year -- this is for a 2005 XJ8L

 

Hi, I wanted to chime in as I am having a similar issue with an 05 XJ8, but slightly different. In my case, the glovebox opens fine with the release button, but when you close it it won't latch. This is because the electronic latch is remaining in the "open" position. I removed the latch assembly from the car and operated it remotely with the release button, and verified the motors moves the latch, but only toward the "open" position. If I push the release button repeatedly it eventually closes, but takes some determination.
It appears that the latch motor runs forward and backward to open and close the latch, but I am not sure how this is accomplished electrically. I thought that the circuit board or the latch motor itself might be suspect, so I bought a secondhand latch assembly on eBay. Unfortunately that unit acts similarly, so the problem must lie elsewhere.

Should I suspect the relay you mentioned in this thread? I did find the interior fusebox in the passenger side kick panel, but don't know what I am looking for. Any suggestions welcome, as driving with an open glovebox is not ideal.

 

The R1a relay is simply in the voltage supply path to the glove box motor along with supplying some other services in the car.
That relay does not trigger the motor to open or close, the signal from the front electronics module is what tells the glove box motor to respond to the glove box button request.

I would have assumed that the likely suspect would be a lazy glove box motor assembly, not returning the latch to the closed position, but you have replaced that with a second hand unit.
Your symptoms would possibly indicate that the glove box switch is not properly releasing. Electrically all that switch does is complete an earth to the front electronics module (connector CR9 pin 2 - Orange wire with green stripe).
You could disconnect the two pin plug to the glove switch (plug IP12) and then just use a jumper wire to momentarily touch between the two plug pins to emulate the glove switch operation to see if you get different motor cycling behavior. If it behaves properly using the test link as a switch, then you have a switch issue that it is not releasing its contacts properly.

If this test still makes the motor behave the same, then either you actually have been really unlucky and have two faulty motor assemblies, or the front electronics module is not releasing the "open signal" to the motor. I would try testing the spare glove box motor on the bench before concluding a faulty front electronics module.
You should be able to separately test the glove motor by applying 12 volts to it and a trigger signal.
Pin 1 is +12 volts,
Pin 2 is ground,
Pin 3 is trigger pin - probably needs 5 volts or 12 volts briefly applied to trigger that glove box servo motor to cycle. (I have never tested one of these motor assemblies, so would try 5 volts first).

 

Is there a diagram to show where the "R1a" relay is? Sorry, I guess this is common knowledge to many here, but I'm a little lost about what R1a refers to.

Is the soldered-in relay being discussed one of the boxes on the diagram below -- or is it somewhere else completely?

https://fuse-box.info/jaguar/jaguar-...se_Box_Diagram

 

R1a and R1b will be located here beneath the fuse box casing.

 

Thank you for your comprehensive reply to my problem. I was unable to do anything until now (darn Covid), but today I was able to verify that the release switch is good by briefly jumping across the pins of the connector as you recommended. (Action the same as using the switch on both actuators).

I also bench tested both actuators as you suggested, 12+ to pin 1, - to pin 2, and (initially) 6V to pin 3. Nothing doing, so I bumped signal voltage to 12V. Same result. Just to confirm that I didn't fry anything, I retested both actuators back in car and both still act the same, they work fine to open the plunger but to retract it one needs to work the release button about a dozen times. Pretty frustrated with this, but not quite willing to give up yet.

You mentioned the front control module directs the action of the actuator. Actually, I replaced the front control module about a month ago with an eBay unit since some of my lights weren't working, and that fixed the problem. However, I don't remember if this glove box issue predated that problem as I may not have tried opening the glove box. Do you think it could still be a front control box issue, or do you think I have a lazy actuator? I hate to keep throwing used parts at the car but that's kind of my only option since the new ones are insanely expensive, when available. Thank you kindly for your advice, it is much appreciated.

 

I was assuming the actuator would need a positive supply voltage to trigger it, but if you set one up on your bench again with 12v to pin 1 and ground to pin 2.........then measure with your multi-meter if you have any voltage appearing on the unconnected pin 3.
If so, then the actuator might instead be needing pin 3 to be briefly grounded to cycle it.

 

Good advice, and I re-ran the bench test. With +12V to pin 1, and -- to pin 2, I am able to read +12V at pin 3. When I briefly touch pin 3 to ground, the actuator moves as it did before, i.e. mostly toward the "open" position, and with multiple touches finally moving closed.

However, when I touch pin 3 to ground and hold it there, the actuator plunger initially moves to to the open position, pauses a second, and then returns to the closed position, just as I imagine Jaguar (or Ford) intended. YAY!

In order to replicate the bench test, I hooked the actuator back up to the car wiring, and tried holding down the release button, but no joy. What do you recommend as my next step, and please accept my heartfelt thanks for your help.

 

If I were designing the part I would have made it that the actuator motor once initiated would not require the trigger pin to be held low to complete the cycle.
I would have built in a revolving contact that gives a 'continue' signal until the rest position is once again reached.......a bit like your windscreen wiper motors do.

So for your issue either you have one of two possible problems....

1/ A front electronics module that is not holding the 'Open' command for long enough - which I feel is not very likely as any driver fault would either be 'hard on' or 'no-go' at all....not a too shorter duty cycle.

2/ The other thought is coming back to a mechanical issue of the actuator - suspecting it might have an incorporated position rotary or cam switch to continue to run then acknowledge home/park position.
Can you safely open the actuator assembly to see if it does have an incorporated switch?
It is nagging me that you have two actuators doing the same thing, but it is not outside the realms of possibility you have two faulty actuators.

If you just want a work around, with your bench testing time the pin 3 grounding duration you need to cycle the actuator reliably, then consider buying or building a simple short duration timer circuit to emulate the time you need to hold pin3 down to trip these actuators properly, intercept and insert that in the pin 3 circuit.

 

I like your idea of a workaround, so I thought about trying to employ the release switch to connect pins 2 and 3. So I reconnected the actuator to the car wiring and with the release button wiring disconnected, tried jumping pins 2 and 3 again. It works! So now I just need to splice the two empty wires from the release switch to the two wires at pins 2 and 3, and I should be back in business. I may need to hold the release button in an extra second when opening the glovebox in order to allow the latch to return to the closed position, but otherwise should be good as new.

 

That'll work.
The reason the glove box actuator is driven via the front electronics module is that it can then be also governed by the security features......effectively locking the glove box when the car itself is locked and also when in valet mode.
If neither of those situations are a major concern for you, then just manually controlling the actuator directly with the switch and pressing it long enough to cycle the actuator will get the job done.
When the car is locked, you possibly do not have 12 volts present on pin 1 anyway, as the relay R1 will probably be disengaged until you roll the ignition key into position 1 or 2.

I still think the actuator (x2) is at fault, so try to do your wiring modification in a way that you can easily reverse it if you decide at some time in the future to resolve the actuator issue.
Bear in mind that whatever the defect is within the actuator, it will probably continue to decline, so your work around may become less effective over time.

 

Thanks, yes I noticed that leaving the door ajar for some time makes the system time out and kills power to the actuator, so I think locking the doors will also. I plan to use tap splices to keep the car wiring relatively unmolested, and if the current actuator fails I still have the backup unit. Thanks again for all your help, you were the only one that responded to my inquiry, and I hope this thread helps someone else.

 

Hi Andyzjag,
We're all part timers here, dotted around the globe....but just members helping other members.
Glad to have been able to help you.
Having an electronics background and having always preferred most of my reading to be technical manuals and schematics rather than novels, I often put my hand up on these types of queries.
Being in an earlier time zone also sometimes give me a jump start on members in other locations.


Meanwhile peterp1, how are you going with your issue?
Sorry your thread got a bit sidetracked there for a while. ;-)

 

Thanks so much for your help! To be fully transparent, @Andyzjag is my brother. We had both been working together trying to solve this problem when I was visiting FL, and then I continued to do more research after returning home. He was doing the same -- which independently landed us both on this thread. I don't think it would have been solvable without your guidance. Thank you again for taking the time to help. Hopefully this discussion will help someone else. It's hard to believe a glovebox latch would be this difficult. Overall, he XJ8L has been amazingly reliable and great to drive, so it's well worth the effort even though this problem was pretty frustrating.

In this case, two heads (ours) were not better than one (yours)

 

Hopefully you and Pete will be able to sit down and have a beer and bit of a laugh about this.
Glad I could help.....a problem shared is a problem halved.

Is the spare actuator able to be dismantled?
Just curious to know if it does have a cam switch or home position encoder inbuilt, so the motor/gearing only goes through one complete rotation to come back to the locked position once triggered.