Thanks to all above for the input and solutions and to Brutal, again, for the original solution. Worked like a charm. Found one on eBay for $160 and cool again. Sweating bullets at first wondering what it would cost. Found this answer on my first search that afternoon. Thanks again!

 

Thanks to everyone for the great info on this problem. AwesomeAuto hit the nail on the head. Ohmed the thermistor and it was open. Back in the 70's I was a TV tech and found many thermistors to be faulty. They are usually an extra protection on a circuit and in most cases I ran across they opened without a thermal condition. Instead of replacing it I bypassed it by soldering in a wire jumper. The circuit is protected elsewhere so this is not a hazard.

 

Can you just override the control with the black and white wire that are actually hot from the white plug next to the fan plug that seems to be a hot circuit?

I know this might be a no no but it could work till the part got in.

 

If you have the part on order I wouldn't attempt to bypass the control. Those "hot" wires are high amperage and could cause a fire hazard.

 

Thanks for all the good advice! I checked a few of the Import Salvages and got the part for $100.00. Since I have the Glove Box out I connected the paort in the parking lot of the Salvage and it is blowing great! The Mechanic Shop wanted to charge me $528.00 to change out the part. What a Rip Off! It only took me 40 minutes to get to the part and pull it out! I love this forum!!!!!

 

Thanks to all the useful information, my blower is working again......

I'm comfortable with electronics, so started ordering the thermal fuse from Digi-key. Part# is P10920-ND, Panasonic EYP-2BN109. Waited for the part, than started working Sunday.....

It took much work to removing the glove box by removing all the screws and fasteners. Frustrated, finally, just push/move everything out of the way to clear enough space to reach the module above the duct work. Looking at the module with the plastic cover preyed open was a little puzzled at the beginning. Trying to determine the best way to get to the thermal fuse as it is clipped onto the heat sink. Finally, I de-soldered the FET transistor at one end, and loosened the screw holding the clip to remove the circuit board. After replacing the fuse, I put module back in the car, plug in the wire and fan is working again!!!!

It took a better part on a Sunday from starting to take panels out to get to the module, to soldering the replacement fuse, to putting things back together. Just remember to wear mechanic's gloves, metal behind dash is sharp...... Got a few cuts myself.

Thank you again for the useful information.

 

The blower control module (BCM) on my ’04 XJR failed in April, throwing a B2514 DTC, Climate Control System, Blower Drive Signal Circuit Fault (I use Autoenginuity with the Jaguar enhanced interface). I installed a new module from Jaguar to address the problem, but not before trying to repair my existing module. The following provides a bit more detail.


1. I followed the XJR Workshop Manual instructions for removal of the glove compartment, as well as advice provided by Glendoramike. One difference was that my car (VIN 30135) does not have a glove-compartment shelf. Instead, it only has the 12V auxiliary-power outlet.


2. I had to remove the electrical connector to the glove-compartment light, despite suggestions that this was not needed. In my case, the lead to the light was wound around a wiring loom above the light and would only allow the glove compartment to drop ~1 in. After removal, I rerouted the wire, which helped glove compartment installation. I also removed the glove-compartment electrical connector, mainly to get the wires out of the way during removal and installation of the BCM.


3. Removing the two BCM hold-down screws was a pain. There is not room above the screws for even a normal stubby screwdriver and the screws are tight. I ended up using a right-angle screwdriver (see photo), which was effective but slow. I removed the electrical connector attached to the BCM after lifting the BCM from the outlet duct. Doing so with the BCM in place would have been difficult.





4. As expected, the thermal fuse was open circuit. I purchased two fuses and two replacement transistors from Digi-Key: thermal cutoff, P/N P10920-ND, $0.74/ea; and transistor, P/N IRF1010EPBF-ND, $2.47/ea. Total cost was $12, including $5 shipping. I also purchased the Radio Shack Solder Assist Tool Kit, P/N 6400087, $13, recommended by EXETERXJ12C, and a Desoldering Bulb, P/N 6402086, $6. While I could have removed the PCB without these, they made the job a bit easier.


5. After removing the PCB, I removed the screw securing the thermal fuse and transistor in place. It was very tight, no doubt to help ensure conductive dissipation of heat from the transistor. I installed the new thermal fuse per the direction of Roberwil and reassembled the PCB. I chose not to install the new transistor at the same time because (a) I was not sure the existing transistor was bad, (b) the new one was much smaller than the existing transistor (see photo) and thus not a direct drop-in installation (as noted by Roberwil), and (3) I was spooked by wondering how a much-smaller transistor could dissipate the large amounts of heat to the undersized aluminum heat sink (I didn’t want a second failure). After connecting the BCM, I checked operation of the blower. The good news: the blower worked. The bad news: it only worked at high and very-high speeds, which was clearly not acceptable.





6. I removed the PCB again and attempted to install the new transistor. I drilled and tapped a new hole for the relocated retaining screw and bent the much-shorter contact legs of the new transistor to line up with the holes in the PCB. However, the retaining screw sheared off during tightening. Given the amount of time and effort it would have taken to resolve this and still having a BCM with the same fundamental design problem, I opted to buy a new BCM.


7. As others have noted, the updated BCM has significantly longer fins (see photo). When I picked up my new one ($190 + tax), the Jag-dealer parts man said they usually have a couple on the shelf since they get requests for them fairly regularly from their shop techs.





8. A quick check of the new BCM showed that the blower worked as expected. It then took me ~90 minutes to put things back together.

 

Great write-up DanJensen,

Here is a similar post on the UK Jaguar Forum. He too came accross the same transistor IRF1010EPBF-ND mady by Toshiba which as you say is smaller than the one in the blower control module (BCM) but he had a electoronics guy confirm and yes the part is simply made smaller now by design and it fits well. This fixed his blower issue and is working fine.



Below article by UK Forum: too good to be true - bah

 

I tore mine completely apart and rebuilt it for around $15.

Here is a write up....

https://www.jaguarforums.com/forum/x...owners-107021/

 

I have the same issue with the blower stop working few days ago even the Climate Control Screen shown the fan is still on. Before I order the new Control Module, can someone tell me where is the fuse that control the blower/Fan? Base on the manual, is that the Fuse F1 (10 AMP) on the Cabin Fuse Box? your help is much appreciate.

 

Hi Ricky,

I'm attaching the schematic for the Climate Control system showing that the blower receives its power via Fuse F7 (40A) in the Rear Power Distribution Fuse Box in the trunk/boot. Assuming that fuse is still good, your problem is almost certainly the Blower Controller / Blower Control Module (BCM).

I rebuilt our Blower Control Module per the instructions in this thread, but the thermal cut-off blew again while idling in a line of stopped cars on a 90+ degree day. I've just rebuilt our module again and added a heat sink with longer fins to see if that will do the trick. I hope to post photos in this thread soon.

Cheers,

Don

 

Hi Don,

Thanks you so much for the information. Just checked the F7 fuse in the trunk and the fuse is still good. One observation, the AMP of the fuse is not 40A but 25A. Is that matter in this case?

I don't recall Dealer change it before and the Blower Fan has been working for last few year. As always, this is a great forum...Thanks !!

 

Hi Ricky,

Are you certain that you are looking at the F7 fuse? On our '04, the left column of fuses in the rear fuse box has nine fuse positions, but the first four positions are empty. The first position that actually has a fuse is F5. On our car, position F7 has an orange 40A fuse installed. F9 is a white 25A fuse; is it possible that is the fuse you examined? If you really do have a 25A fuse in position F7, I would assume someone has installed an incorrect fuse. But if the fuse is still good, it's probably not the problem with your blower - that is almost certainly your BCM. You can test this theory by jumping across the two large black wires in the white electrical connector that connects to the BCM. With those wires, jumped, turn the key to Position II and turn your climate control system on, and the blower fan should run, but only on HIGH regardless of the position of the fan control knob. See post #28 from sleepyastronaut in this thread:

https://www.jaguarforums.com/forum/x...-working-8322/

If the fan runs when the connector is jumped, then either the thermal cutoff or the power transistor in your BCM is fried. These parts are very inexpensive from DigiKey but you need some basic desoldering and soldering skills to make the repair. A local electronics repair shop might be willing to help and shouldn't charge too much, and the information in this thread makes the job easy.

With the connector jumped, you can run the A/C as needed until your new BCM arrives or you have the original one repaired. As long as you use a decent piece of wire for your jumper (I used 14 awg) it won't overheat.

Cheers,

Don

 

Hi Don,

you are certainly right, I look at the wrong fuse.

The fuse was good, so ordered the new BCM unit from eBay for $165 (made in Japan) and put that in last night. Test drive it and the AC start blowing again.. Thanks for saving me again !!!

It doesn't have much room to remove the 2 screw from the BCM unit, have to use L shape screw driver to get it out. Also, I didn't unplug any of the electronic connector.

 

I just performed this job using the instructions from the OP and the blower is now operational again. I was tempted to repair the original module but decided to go with the upgraded part with the larger fins. If it happens again I may try repairing the part. Thank you for the excellent write-up and diagrams. I would have most certainly missed those two little phillips screws without the information you provided.

 

You can order a new module with the longer fins for 200 including shipping here---->
Jaguar 2003 09 XJ8 XJR Front Blower Motor Resistor Control Module C2C39577 | eBay

 

Or, you can rebuild your existing module, including a new heat sink with longer fins, for about USD $20.00.

https://www.jaguarforums.com/forum/x...t-sink-126502/


Cheers,

Don

 

Hey bud! Do you have any of these parts left? My blower just went out. Thanks!

 

Hi TP'sXJR,

Note that VDPBlue made that offer in 2012. He may not check this thread again, so you might try sending him a private message with your request. Worst case, you can order the parts directly from DigiKey for less than $10.00 including shipping (DigiKey Electronics - Electronic Components Distributor), though I would advise you to order a few extras of each part since they're inexpensive and likely to fail again, unless you also upgrade your heat sink to one with longer fins.

Cheers,

Don

 

Thanks for all the info Gentlemen. Just installed my new module today and my air is working once again.

Regards
T B