My right rear turn signal functions properly until I apply the brakes then the brake light over rides the turn signal. The left brake/turn signal works normally as does the fronts.Anyone have any ideas. Thanks in advance for all replys. Vehicle build date 1/94.
Gary, check the ground point on that unit, generally when a light ātake overā it is because the current is looking for a return route.
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Thanks Robin, I will look into it tomorrow and see what I can find.
Hi Robin
Based on your suggestion I swapped the tail light circuit boards left for right to see if the problem followed the board, which it did not. I assume that means the problem is in the hard wiring somewhere. Could there be any chance that something in the front signals could affect the proper functioning of the rear brake/turn signal? Anyway, my car is in the shop right now for a 4 wheel break job so wish me luck on that one. I will investigate further when she is back home. Thanks again for your help.
Gary
Just to confirm, did you swap the lights or the BFMās?
I unpluged the circuit boards and swaped them side to side with bulbs in. Excuse my ignorance but what is the BFM, a module of some sort.
BFM= Bulb failure module. There is one at each corner of the car. They can be problematic as the circuit board solder connections can go bad.
As John has stated they are the black box at each corner of the car, these are grounded which you will have to disconnect to change side to side, the fronts are different so cannot be used. However changing the BFMās may actually cause the fact to go away as the grounds will be re-connected.
Again as John states they can have dry joints which can be re-flowed to remake the circuits.
Thank you John and Robin for your input. Today I disconnected all the ground wires and cleaned them. No difference. I then swapped sides with the BFMs (my new terminology, thank you John) and still no change to my problem. I also changed the blue relay attached to the right side BFM mounting bracket, nothing. After a visual inspection of all the wiring inside the trunk area I noticed nothing suspicious. Assuming itās not a ground fault what else could cause the break light to not know that the turn signal is on, the turn signal switch itself, is there a remote turn signal relay somewhere?
As always any suggestions you my have will be greatly appreciated
Sorry Gary run out of ideas on that one. Bryan N any ideas?
You may have a cracked or cold solder joint on the rear bulb receptacle circuit board. If all else fails and you want to give it a try, access the circuits by melting the plastic tits with a soldering iron. Then you can and pry the board off the mounts. Reflow the solder then re-assemble by remelting the tits to secure the board.
This has worked on my car - I had a problem with LR running light - slightly different issue but the reflow cured it.
Not really - but just to clarify Gary.
You swapped the BFMs and the fault stayed on the right side?
You swapped the circuit boards INCLUDING the bulbs and the fault stayed on the right side?
That being so the fault cannot be in the right BFM or the right circuit board / bulb holders?
That blows my original thought that the fault may be something to do with the dual filament stop and turn signal bulb. Try swapping the right one out anyway.
As far as I know, the ground points for both the turn signal and the stop light are the same so I canāt see the problem being there but it may be worth checking continuity to ground from pins 1 and 5 of the five-way white connector at the tail light
To add insult to injury I went to start the car after messing with the tail lights and it cranks fine but will not say a word. I am working on this alone so I havenāt been able to check for spark yet but I canāt imagine how that could be related to tail lights. Iām thinking maybe when taking out the trunk liners I disturbed the fuel pump wires. There are 2 inline fuses that I have no idea what they are for, power antenna maybe, but they tested good. Anyone have ideas on this issue? Some days just donāt pay.
Gary,
You mentioned previously replacing a relay on the right rear BFM bracket.
That is the fuel pump relay (in a black base). check that out as a possible source of your non-start problem.
Turn on key but dot turn to crank positionā¦You should be able to hear the fuel pump HMMM for a few seconds if you hear itā¦ the HMMā¦ (thatās fuell pump) not sure if you have a pressure port on your fuel rail but after hearing the fuel pump carefully check the pressure port schraeder (with ignition off) for fuel pressure which should remain in the rail for some time after ignition is off
If yo have no fuel port-schraeder portā¦ loosen a fuel fittingānot too muchā, wrap fitting with towelā¦ and turn on ignition just once , but donāt try to startā¦ turn off ignition should be fuel at the loosened fitting? If so maybe injectors not firing and or spark issue. Though the gas fuel pump test wont tell you what the PSI isā¦ I assume the no start happened ā¦ fastā¦
I finally got back to my fuel pump problem. Bought a new relay to start these tests with. Did a continuity check at the relay socket with rely removed, battery disconnected and all 4 wires go straight to ground. Did a voltage check at the relay socket with key in position 1, post 30 at 12v, the others 0. Key in position 2, post 30 2.4v others 0. Identical results doing tests with shifter in drive as in park. Ran continunity check on wire from relay post 87 to fuel pump and that wire had continuity.so I ran a hot wire from post 87 to the fuel pump and pump works and car runs.
This may not be a good idea but if I find a source of 12v that runs through the key can I connect it directly to the fuel pump and if so would it have to come off of key position 2 or 2 or both. As always I appreciate any advice, insights, suggestions, etc. anyone my contribute.
Gary
Gary,
Tried to follow your circuit test info using the fuel pump circuit diagrams but canāt reconcile your results with the way I think the circuit works.
Firstly, with the relay removed, Pin 87 of the FP relay base always goes to ground via the fuel pump itself and you say you have continuity on that wire as far as the fuel pump.
When you say - āI ran a hot wire from post 87 to the fuel pump and pump works and car runs.ā, donāt you mean that you ran a hot wire TO post 87 of the relay base? That would put 12 Volts directly on to the pump so it would work.
You then say - āKey in position 2, post 30 2.4vā. That confuses me because with the relay removed, post 30 of that relay base should be getting battery voltage, 12 Volts, at all times direct from fuse C6 in the right side fuse box. The feed to that post 30 is not Ignition-switched so the key position should not be relevant.
With the relay removed, post 85 of the relay base should be permanently at ground.
With the relay removed and the ignition off, post 86 of the relay base should be open circuit but with the ignition on with the key in postion 2, you should see battery voltage, 12 Volts from fuse C4 in right side fuse box at that post 86 fed via the Oxy Sensor heater relay.
Please try to sort out the circuit as designed before resorting to direct ignition switched power to the fuel pump.
Hi Bryan, thanks for yo
''ur reply. Yes, what I had done (Ā“āļ½)
.a, run a hot wire to the relay socket for pin 87 and that woke up the fuel punp. All else was as I described. I could not locate the inertia switch but since I get 12v at the relay with the key in position 1 I assume voltage is flowing through it. I will check the fuse you mentioned tomorrow. Would there be any kind of control module that could be fauling up the voltages to the relay?
Thanks for the time and effort you have put into helping me.
GaryQ&A
Gary,
Not that I am aware of - but Iām not a āsparksā, so perhaps someone on the forum who is can explain why you are only getting 2.4 volts at post 30 of the relay base with the relay removed since you should be getting battery 12 volts direct from fuse C6 in the RH fuse box.
The only thing I can think of is that perhaps you have a high resistance bad solder joint behind fuse C6 causing that voltage drop . Clearly when the FP relay is energised to put voltage from post 30 across to post 87 and hence to the fuel pump, 2.4 volts is not sufficient to drive the pump.
HI Bryan
Checked fuse C6 this AM and it was blown. replaced with new and now have 12v @ post 30. Still no juice (0.02v) at other posts at any key position, even checked it with tranny in D. What is the source of voltage that activates the relay to send battery voltage to fuel pump?
I really do appreciate all the response I have been getting from the Forum.
Gary