I get the same problem with lights on.
What box?
I will check the park neutral switch and will also check the shutter.
Thanks for the help.

 

There is a light sensor box on drivers side wall of trunk. Brake and tail lights connect to it. When one light fails, sensor on dash comes on.

 

Ok so I removed the brake light sensor box, I have no brake lights and the R does not light up when brake pedal is applied and R does not light up either and the dash sensor is not on either and the kicker is the shudder is gone when brakes are applied around 20 mph and the rpm's do not drop either. I got another brake light sensor and when installed the sensor light on dash is gone but the R is still coming on when brakes applied and the shudder is back again too. So Toyomoho what the heck do you think is going on with my camry? I will try to unwrap the wires by the driver side hinge in the trunk tomorrow, hopefully I get lucky with a broken wire. Also I have no shudder when I don't apply the brakes and car comes to a stop, like going up hill. Thank you for all your help.

 

Wiring problems are of course difficult to diagnose, more so over the internet. But will give it a shot.

If removing the box eliminated the shudder problem and RPM drop consider this making progress in narrowing down the problem area.

Guessing a wiring problem, short, two wires now touching due to damage, bad ground point of a wire, ?

Many people have just removed the box and rewired around it. However, a bad box affecting transmission or engine operation is new to me, but not to say it can't happen.

For now, it appears some circuit(s) connected to the box have a problem. The task then becomes finding this circuit(s).

By disconnecting circuits you may be able to determine which one(s) cause your problem.

Suggest starting by disconnecting the wires going to the Gauge fuse and dash indicator light. It is possible power is feeding back through the fuse into the dash causing strange problems. Be sure to tape over these wires as they will be hot when ign switch is on.

If you want, also rewire the brake switch wire directly to the brake lights wires to bypass the box.

Then go for a test run where at least you should have brake lights.

My guess is this may solve your problem, but?

You can then try a combination of wiring connections Gauge, upper brake light, etc. to find out what eliminates the problem and causes it. Also determine what works. As in brake light no longer goes out when this or that wire is connected, disconnected, etc.

Then if possible physically inspect the wiring of those circuits.

The wiring for the box is below. This doesn't mean your car may not have different colored brake and tail light wires. For these inspect the wiring to the bulb sockets for colors.

Green/White = From stop light switch.
Red = upper brake light.
Red/Blue = Gauge fuse.
Yellow/Green = Dash light indicator, then goes to Gauge fuse.
Green/Red = Lower stop lights.
White/Black = Ground.

The box White/Black wire and lower brake lights grounds connect at a junction box. The upper brake light ground wire runs to its own junction box. Both boxes then run to ground AND are also connected to each other by wire. If you think it is a brake light circuit ground problem check ground connections (ohm readings) between all light grounds.

For the taillight wiring of the box:
Green wire = incoming power from taillight switch.
Green/Orange = tail lights

Like the brake light ground wiring. All taillights that receive power from the box have their grounds wired together and have multiple chassis ground points.

If the issue is the Gauge fuse or indicator bulb wiring not sure what to do. As a temp fix can wire brake and tail switches direct to appropriate lights. Then leave Gauge and indicator bulb wiring disconnected but tape over as these have power.

Many an owner has done just this when the box become a source of too much frustration.

Try the above then post back with results.

 

Thanks for the great advice Toyomoho. I will check it tomorrow.

 

Thank for the reply toyomoho!


Mine is the 2.2L 4 cyl, Camry LE w/ac. Took it for a run yesterday and found it made no difference if the OD was engaged or not. The shuddering problem seems to be speed specific. The vibration seemed to be slightly more pronounced with the OD engaged.


When I step on the gas, the RPM increases accordingly and the car struggles to increase the speed while shuddering.


Crazy as this may sound, I find the problem to occur most notably when I hit the 50-55mph range. While in that speed range if I put my foot to the floor sort to speak, the car shudders like crazy, slowly increasing speed until I lighten up on the pedal after getting up to the desired speed.


Addt'l info: Timing belt has never been changed (car has 41K original miles driven by Grandpa all these years!). I can't emphasize enough that the problem is most prominent at the 50-55 mph range. Could this be a mechanical front end problem?


Thanks in advance for your opinion!

 

Sometimes the EGR valve opens too much. If can find the vacuum line to the control valve on top of the EGR valve, disconnect it and plug the hose. This will turn the valve off.

Or plugged emissions converter.

Perhaps a bad coil. Spark should be white in color and able to gap 1/2 inch of air.

 

I had the same problem no Reverse lights or R lighting up on my shifter. I have a 1993. It was a problem with my Neutral Safety/Backup Light Switch. See attached pictures of the problem areas. What I did was sanded the one bar down that had the grooves to make it flat again. Then use like 1000 grit to give it a smooth finish. Then use the electrical grease it all up.
Also don't worry NO transmission fluid will come out when removing.

Also attached is the diagram to test your switch.