well, today my o/d worked and light was working, i noticed on my way home today the light wasn't working at all, not sure if o/d was kicking on or not, wasnt going fast enough, will find out tomorrow. anyway to check if the bulb is just burned out?

 

went for a drive around the block. tranny seems great, o/d is working properly and button works, changing it in and out of o/d just fine. looks like my bulb is burned out.... how hard is it to replace the bulb, taking the instrument cluster out?

 

Its not hard, you just have to unscrew a lot of panels to get to it. Keep check of where the screws came from and you will be fine.

Check out this page for notes and photos on panel removal:
http://www.geocities.com/craigbraceg...ock/clock.html

 

alright, so I took apart my dash, checked the bulb, its fine...I swapped the o/d bulb to the security spot and it was working, put it all back thinking maybe a bad connection or wire on the shifter. tore that apart, checked continuinity and voltage at the wire going from shifter to harness and the harness to ecu or dash, i have no idea where it goes(goes under carpet). all seem in spec except that I should of got about 12volts when the o/d was off, but I got 8.5volts. 0volts when it was on, which is right.

only thing that I could think of is maybe a wire got fried on the back of the instrument cluster? o/d on the tranny still works properly. or maybe 8.5volts not being enough to turn the light on? dont make sense to me tho. any help is appreciated.

 

why are you even turning your OD on or off?
are you towing with the car?
if not then leave it alone! let the trans do its job.

 

no im not towing. i've been told to have it in the off position when going up and down alot of hills, this keeps it in 3rd gear right? where should I leave it?
but anyhow, im sure your right, and ill take your advice and just keep it on, but I have this problem now.

you think its the instrument cluster?

 

it will leave it in 3rd gear.
but it hurts your mileage when going down the hill.
of course I live in chicago and we have no hills

 

There's nothing wrong with switching it on and off. If anything, the golden rule I go by is O/D off below 80km/h, on at 80km/h and above. Reason being, the 4th gear clutches in a stock box just don't appreciate it despite the fuel economy and comfort you gain from it. Many a 4th gear clutch packs have their life shortened because of this.

Even with mine having being rebuilt by Level 10 7 years ago to a PTS3, I still drive it the same way. It's TLC to me.

 

ya i didnt think using it was too much a problem.

anyone got an idea on what could be causing it? think ima rip the dash apart again this weekend and take a closer look

 

Ok, first of all it's "should've" or "should have". No such thing as "should of". Sorry, it's just a pet hate of mine when I see or hear that being communicated. 3#-)

Anyway, secondly ... depending on how you measured those voltages, you should be seeing 0V when the O/D switch is off (which is when your bulb should illuminate) and close to battery voltage when O/D is on (when your bulb should be extinguished) with respect to ground (i.e. having the negative lead of your multimeter on a known working ground such as a bare metal frame, ignition key barrel, etc). Otherwise, if you measured across the terminals of the bulb connector whilst the bulb was plugged in, then you've got your measurements around the right way but 8.5V is pretty low.

Reading your message a 2nd time, I've realised that you measured with respect to ground from the shifter's connector. In which case, you've got your measurements around the wrong way. You would've seen 8.5V with the O/D on and 0V with the O/D off.

Now then, if all you were seeing was 8.5V when the O/D was off (or on, depending on how you measured it), then it is possible that:

* TCU (A/T computer) is drawing a little bit of current out of it, weighing it down as a result
* the wiring between the ignition line and the bulb is not up to scratch (although that would affect all the bulbs in your instrument cluster)
* the track leading up to the O/D bulb itself is most likely not up to scratch (as opposed to the 2nd possibility I just mentioned)
* the connector for the bulb is not making a good contact

Now then, you've already done one step in the process of elimination and that was to test the bulb in another socket. That's good and reassures you that the bulb and base themselves are OK.

Just in case, start simple and unplug your O/D switch from its connector and short the two pins out. See if it now illuminates. If it does, you've got a bad switch (even though it's good enough to tell the TCU to enable O/D).

Otherwise, that leaves us with the contacts on the instrument cluster itself as one possibility. What you should do is, with the bulb taken out, set your ignition to the ON position and check the contacts on the instrument cluster with your multimeter with the overdrive button ON (as though to engage 4th gear). You should then see 12V across it. Switch the O/D button off to confirm that the 12V doesn't remain, just in case. If you do see this voltage across the terminals, then it's most likely something bad with the contacts between the bulb base and the instrument cluster. Try another bulb from another indicator socket to see if maybe that socket just no longer likes the O/D bulb's base. Stranger things have happened!

If you do not see the 12V across those two contacts, on the other hand, then you'll need to check that you have at least 12V appearing at one of the two contacts, with the negative lead from your multimeter making contact with a known earth, like the ignition key barrel. If you see 12V there, then replace the bulb in the socket, jumper a wire from a known ground (such as your ignition key barrel) and see if the bulb then illuminates. If it doesn't, the problem is in that area alone. If it does illuminate, then you should jumper a wire from the switched (not the grounded) terminal of the O/D switch to the ground terminal of the bulb contact on the instrument cluster. If it does illuminate in accordance with switching the O/D switch off, then you definitely have a dud wiring problem between your bulb contact right through to the switch itself. The wire colour is the same from start to finish (green with yellow stripe). With the O/D switch in the off (i.e. grounded) position, keep the negative lead of your multimeter on a known good earth (such as your ignition key barrel) and test every possible contact along the path from the bulb contact, any test points along the track on your instrument cluster, the contact of the instrument cluster female connector (it's pin 35 if you have an FSM diagram handy - or just find the one with the green with yellow stripe wire), the contact of the instrument cluster male connector off the harness, right through to the contacts of the switch itself.

Basically, follow the path from start to finish and you'll eventually find your culprit.

Have fun and good luck.

 

thanks a bunch man. will be doing that this saturday, will update

 

it's an automatic so I let it shift it self. Never had a problem of feel like it is in 4th when it should not be. I had a friend that always played with his O/D and ended up frying his tranny. The bulb probably went because it was not designed to be constantly played with.

 

I think his tranny was already well on it's way. The overdrive switch is there for a reason. To keep your car from going into the last gear in the event you'd want the higher RPM's for passing or accelerating and stopping quickly without constantly shifting in and out of o/d.

I messed with mine when I needed to on both of my cars and the transmissions are fine. My dad never ever messed with the O/D button in his VG and he went through 2 transmissions.

The instrument panel/shifter assembly just probably has a short somewhere. As long as it's working I wouldn't worry too much about it.

 

re-read previous posts....the bulb is fine, I checked it in a working socket on the cluster and it lit up, but don't work in the o/d spot

 

i am not saying that you should not use it but it is something that you should not have to use it everytime you go up a hill or everytime u drive the car.

 

1) That is not why his tranny fried. What do you think the tranny does when you go wide open throttle from 4th gear at 60mph? It backs down to 3rd and does it with a bit more force, placing a bit more strain on the clutch packs. So doing it at a more moderate engine speed is not going to do it any harm. Essentially, your friend's tranny fried because it was already set to fry. My first tranny fried at the 70,000km mark (thankfully still under the extended warranty) and the first thing to go was the 4th gear clutch pack because I never took the O/D off. Since then, I'd driven with the O/D off and on as the road conditions dictate and not a single problem with it. If Nissan programmed their TCU so that in power mode it doesn't shift until 80km/h, then I wouldn't have so much of a problem with it. Actually, that gives me a thought ... I should design a circuit that will manipulate the O/D button for you at those speeds with the O/D button still being active as an override to switch it on if still manually required.

2) His bulb hasn't gone out. He has a connection issue.

 

In his case it WAS. HE had some sort of electrical failure I don't remember the details. If I find out I will post.