HUD/Analog Gauge cluster fix found... PICS...sticky please!!...:)

[amolao]

I searched in many groups about my cluster problem to no avail. I just installed an HUD cluster on my 1989 S13 SOHC.

Symptoms: a week later after cluster installation, I try to shut my car off and all my ACC items will stay on, radio,heater, cluster lights,etc. I thought it was a ignition switch problem. I try restarting the car and it went away...but later that day I noticed that the driving lights and cluster lights were still on, even with the lights switch off and the flip ups were staying up permamently...Something was shorting my illumination path to ground. I went directly to the cluster and double check the harness just in case. I found that by disconnecting the cluster the problem went away...I never trouble shoot a cluster of any kind before, and would like to share my findings.

Troubleshooting: Is not too much to it, and it applies to analog/HUD and maybe even DOHC cluster. Measure all the diodes in the back of cluster. If you find any that are shorten out, replace them. I used old ones from an analog cluster I have for parts. The diodes are the same. Check the pics for the location of the diodes. They handle the illumination of the cluster and clock. Also tied up with the car light system. If you can find an FSM, look up the wire diagram, these two diodes are tied up on one side and by shorting out they were grounding the lights on the car, also confusing the time control unit and creating other issues...flip ups staying up and the ACC function staying on.. After replacing the diodes, all problems solved. Ensure if you have an HUD that your connector for the HUD LCD module is on, if not you will not have cluster illumination. Also to have the blinkers switch connected if not you will not have turn signals, just to keep you from getting confused during final testing. Sorry about the long post, hopefully somebody outhere will benefit from this. And now the pics......

Here you can see the location of the specific diodes and the cannibalized analog cluster, plus a top view of my shoe....

A good look of the flex mat circuit board, BE CAREFUL when handling this part is very delicate....also ensure that you maintain the polarity of the diodes, they only go one way and one way only.

An even closer look, not a perfect soldering job, but it will do....Also you might notice that I soldered the diodes in the wrong side of the board, I had to because I used the old diodes and cut them off from the other cluster and they were too short to be soldered on the back of the HUD cluster. But actually is better this way, because if you need to replace them in the future you will not have to take the circuit board and all lightbulbs to have access to it...just make sure they dont touch any metal in the dash when installed....

Just to give an idea what tools you are going to need......do not apply too much heat to the components or you will damage the tracks on the flex circuit board.....

Any other questions feel free to email, my fellow NICO brothers.........

[onosqv]

VERY NICE, but I need more detailed instructions .

First off: How am I suppose to measure the diodes? I only know the very basics of multimeter usage, and don't know what the diode readings are suppose to be or where to put the black/red probes.

Secondly: Which way is the one way that these diodes go? I haven't checked out my cluster lately, but I don't even remember having those two diodes in the HUD cluster - I have an 89 240sx w/ HUD also. Are these diodes you added or were they already on the cluster?

Third: There is only 1 kind of diode you can buy at a store (i.e. Radioshack) right? If not, what kind do I need

THANKS Amolao

[amolao]

VERY NICE, but I need more detailed instructions .

First off: How am I suppose to measure the diodes? I only know the very basics of multimeter usage, and don't know what the diode readings are suppose to be or where to put the black/red probes.

Secondly: Which way is the one way that these diodes go? I haven't checked out my cluster lately, but I don't even remember having those two diodes in the HUD cluster - I have an 89 240sx w/ HUD also. Are these diodes you added or were they already on the cluster?

Third: There is only 1 kind of diode you can buy at a store (i.e. Radioshack) right? If not, what kind do I need

THANKS Amolao

Very good questions, .......

When you measure diodes, with a multimeter you are looking for a high (ohm) (open circuit)resistance reading with the meter leads measuring across the diode. You will not need power on the cluster to measure resistance (ohms). Now inverse the location of the leads and you get a low (close circuit) resistance reading or almost 0 ohms.....With the bad diodes on my cluster I was getting 0 ohms both ways which indicates a short condition which is not the way diodes work...therefore acting as an piece of wire and grounding the circuit and creating all kinds of fun...

If you like, find a diode somewhere and check it....just for practice and to get an idea of what to look for....they work based on polarity (+) and (-) so by reversing the leads you are simulating the two basic operational conditions of a diode......If you look at the diode theres a little silver band or mark (indicates negative side) on them...thats what you use to orient the diode, so remember which way the original one was facing and make sure the new matches the same orientation.....

When you take the circuit board off the cluster you will see the resistor and 3 or 4 diodes (depending of what type cluster), they are in the back of the flexible circuit board...I replaced the diodes on the original locations of the bad ones but on the opposite side, so instead of being on the inside now they are on the outside...better cool down

Im trying to track the diodes by the markings, should be no problem matching these with a commercial replacement...when I find the right replacement I will update the thread. I see your point, without an extra cluster or parts there will is no way you can repair it...I think a lot of people have lights problem and go crazy thinking something is shorten out, bad switch or miswire when is actually the cluster on the car

After inspecting all the diodes on the cluster, I noticed that they tend to get pretty hot, which might be the main reason why the fail after a while...so make sure when you replace them that you leave enough spacing between diode and circuit board ( bend the diode legs before soldering to where the diode sits high on the circuit) so the heat does not damage the circuits.....

hope this helps

Modified by amolao at 1:01 AM 1/4/2005
Modified by amolao at 1:01 AM 1/4/2005

[amolao]

brokeAs240sxWhat problems are you having with the your cluster anyway....???

[onosqv]

brokeAs240sxWhat problems are you having with the your cluster anyway....???

Thanks, that should help me well on my way once I start to get to play w/ my cluster . This has also been by far the most helpful cluster troubleshooting thread I've run across all over these boards. I've never taken the circuit board off being afraid I'd ruin it or playing w/ the diodes (usually just melted away plastic on top of circuit and soldered a piece of wire over the burnt area).

Anyway, I have 2 problems:

1) My cluster lights don't come on w/ parking lights (they are on w/o parking lights for "day mode" but not for "night mode"). That one I think may not necessarily be the cluster, because if I jiggle the harness behind the cluster, the lights will come on, but will eventually turn off again.

2) My digital speedo works but does not illuminate (so I still don't know how fast I'm going, haha). I know it works because the odometer still moves, but the led does not work most of the time. I had my speedo working for about 6-9 months (after buying a used cluster to replace my dead one) then I shorted my alarm system, a whole bunch of stuff messes up. I think the alarm is relatively fixed for now, I'll have to see in 2 weeks after I get it back .

Thank you much!

**edit: o yea, i second that nomination for a sticky (included w/ your second post to make it even better) **

[amolao]

1) Check your wiring harness and make sure is secured to the cluster...

2) You have a defective HUD module, even if the odometer works your HUD might be dead...An idea will be to try to make a good one with the two modules you have now...the module comes apart in three individuals boards, just juggle them around and test....maybe you get lucky or try the famous fix that everybody knows about it...(the bad capacitor one...)

[amolao]

Oh and thanks for the STICKY nomination.....

[AZhitman]

We'll add this to the "articles" section soon (some changes coming).

Nice work man!!!

[amolao]

thanks

[will83]

I pulled out my cluster today and going to borrow a ohm meter tonight, if I infact find a bad diode..or one that doesn't measure correctly what "size??" do I replace it with, I do not have a spare cluster. thanks

[doriJDM180SX]

would getting a new circuit board from nissan solve it?

[po boy]

maybe you get lucky or try the famous fix that everybody knows about it...(the bad capacitor one...)

What is that? Details please.

[will83]

tried to fix my digital one but the circuit board looked burned up, put in an analog one from the junk yard, everything works except the odo and trip...so ill be taking it back out soon as i find a good one.. oh well

[amolao]

Yes but Nissan only sells the complete assy circuit....and it will cost you..I gotten two from them (SOHC and DOHC) and is a fix for sure........and Im talking about the circuit panel for the speedo.....the backing flexible circuit shown on my pics is also available and also will cost you...is not that hard to repair if you are good and careful while soldering the components....

[Omega47]

I...F***ING...LOVE...U...

You know how long i have been searching for this,you have perfect instructions with pics,your a god,thank you *hands you a cookie*

[amolao]

Im glad it help somebody......thanks