2007 Camry Instrumentation ghost

[sgelpel]

I have a 2007 Toyota Camry that has intermittent instrument cluster problems. The Speedometer and Tachometer will cease to indicate proper readings and drop to zero. The tachometer will then bounce between zero and what I can only assume is a close approximation of the actual engine RPM. At the same time, the ABS and parking BRAKE warning lights illuminate and stay on for the duration of the "episode". These last anywhere from 10 seconds to 10 minutes. In the meantime, the car runs normally from what I can discern. I can be driving down the highway at 70 or sitting in the parking lot idling and these episodes occur. There are no other indications that something is amiss...no rough idling, no engine stalling, just the display. This is a 2007 Toyota Camry, 4 cyl, 5 spd automatic. I have inspected the transaxle input and output shaft sensors and they appear to be in good working order. There are no indications of oil buildup or broken/shorted wires. Connections all look good from what I can tell.

[lancedon]

It seems as if a Sensor on the vehicle is Malfunctioning, you will have to do a Diagnostic so as to identify which one. I had a similar problem once where one of the speed sensors on the front wheel of my Camry was malfunctioning which caused almost the same problems as you are experiencing.

[Glenn8963]

start with all the basics first.

make sure both battery cables are CLEAN, and make sure the battery posts are CLEAN as well. check all under the hood for broken, loose or missing ground wires/straps. if possible, get up under the dash and look for any loose ground straps.

an intermittent electrical problem can cause a lot of grief, and not too many shops want to spend any time working on them as it is costly, and not only that, but the problem may never manifest itself the day(s) it is in the shop.

also, have the battery fully charged, using a real battery charger, then load test it. sometimes a weak battery can cause problems.

it is always best to start at the beginning of any electrical problem, rather than think or assume it is a major fix/repair.

[sgelpel]

I know that there is a air pressure sensor that is malfunctioning on the Driver side front wheel. I have not replaced that yet, in lieu of these other fixes. I wonder if somehow these could be related.

[igbeserk]

sorry for hopping on this post. my car is giving me the vehicle speed sensor error code p0500. so the code has to do with the sensors in the tires? and just have to determine which one it is? my battery cable and post are clean very well taken care of. i've been getting intermittent issues lately where the brake, vsc, tcs, abs lights will come on and stay on. sometimes the check engine and airbags will do the same. sometimes powering it off and powering it back on helps. sometimes i have to drive with them on for a while then cut off and cut it back on. it'll go away.

so i'm at a loss was looking online for where the actual sensors are but if they're in the tires then i'll check to see what's going on there. maybe best to replace all the sensors. i dunno.

[Luna2]

Originally Posted by igbeserk

sorry for hopping on this post. my car is giving me the vehicle speed sensor error code p0500. so the code has to do with the sensors in the tires? and just have to determine which one it is? my battery cable and post are clean very well taken care of. i've been getting intermittent issues lately where the brake, vsc, tcs, abs lights will come on and stay on. sometimes the check engine and airbags will do the same. sometimes powering it off and powering it back on helps. sometimes i have to drive with them on for a while then cut off and cut it back on. it'll go away.

so i'm at a loss was looking online for where the actual sensors are but if they're in the tires then i'll check to see what's going on there. maybe best to replace all the sensors. i dunno.

First the sensors in the tires are fo air pressure and temperature, not speed.

A code P0500 is "Vehicle Speed Sensor "A""
The speed sensors detect the wheel speed and send the appropriate signals to the skid control ECU. (ECU is the processing control computer module.)

The skid control ECU converts these wheel speed signals into a 4-pulse signal and outputs it to the TCM via the combination meter. (TCM is the transmission control module / computer.)

The TCM determines the vehicle speed based on the frequency of these pulse signals.

When a code P0500 is detected the following conditions must be meet;
When the ECT sensor is normal and the counter gear speed is 300 rpm or more, the vehicle speed signal is not input for 2 seconds or more.(the ECT and CS sensor is inside the transmission.)


Trouble Area;
Open or short in vehicle speed signal circuit,
Combination meter,
Vehicle speed sensor (Brake control system),
Skid control ECU (Brake control system)
TCM (Transmission Control Module)


Monitor Description
The TCM assumes that the vehicle is being driven when the transmission counter gear indicates more than 300 rpm and over 30 seconds have passed since the park/neutral position switch was turned off. If there is no vehicle speed signal with these conditions satisfied, the TCM concludes that there is a vehicle speed signal malfunction. The TCM will turn on the MIL and a DTC will be set.


You indicated the following problem;
"I have a 2007 Toyota Camry that has intermittent instrument cluster problems." (Intermittent problems are very hard to locate. If it don't act up during the diagnostic time it will not be broken.)

"The Speedometer and Tachometer will cease to indicate proper readings and drop to zero. The tachometer will then bounce between zero and what I can only assume is a close approximation of the actual engine RPM." (This is a very good clue to pass on to the service department as it will help a good tech determine the suspect component.)

At the same time, the ABS and parking BRAKE warning lights illuminate and stay on for the duration of the "episode". These last anywhere from 10 seconds to 10 minutes. (Cause and effect here...)

In the meantime, the car runs normally from what I can discern. I can be driving down the highway at 70 or sitting in the parking lot idling and these episodes occur. There are no other indications that something is amiss...no rough idling, no engine stalling, just the display. (You may have identified the problem here. The multiple power sources that feed the combination meter may be of suspect.)

This is a 2007 Toyota Camry, 4 cyl, 5 spd automatic. I have inspected the transaxle input and output shaft sensors and they appear to be in good working order. There are no indications of oil buildup or broken/shorted wires. Connections all look good from what I can tell. (The transaxle input and output shaft sensors are inside the transmission and are only accessible from the plug to the TCM or tearing apart the transmission.)

Test Procedure
READ VALUE USING TECHSTREAM (VEHICLE SPEED)

(a) Drive the vehicle and check whether the operation of the speedometer in the combination meter assembly is normal.
HINT: The vehicle speed sensor is operating normally if the speedometer reading is normal.
If the speedometer does not operate, check it by following the procedure described for a speedometer malfunction.

(b) Connect the Techstream to the DLC3.
(c) Turn the ignition switch to ON.
(d) Turn the Techstream on.
(e) Enter the following menus: Powertrain / ECT / Data List / Vehicle Speed.
(f) Drive the vehicle.
(g) Read the value displayed on the Techstream.


OK:
Vehicle speeds displayed on tester and speedometer display are equal.

NG>CHECK COMBINATION METER ASSEMBLY (SPD SIGNAL WAVEFORM)
OK>SYMPTOM SIMULATION AND DTC CHECK


It will be at this point if the system is working "normally" there will be no problems to fix...
The green highlighted items coupled with what you described about the Tach and speedometer actions will tell the tech where to start looking.

The more information you can describe about the symptoms the faster the repair will proceed, provided the Service Adviser, translates / writes it down properly AND the Service Tech understands those description(s).

I wish you luck in the speedy correction of this problem.
Please post the correction, when completed.
(Have you tried "Ghost-busters" or an "exorcism"?) (JK)
I know what you are (or will be) going through, as I have an intermittent "Shift Flair" between 2nd. and 3rd. that has not been found for 29,000 miles and who knows how many trips for the repair...

[igbeserk]

ah thanks for the info man will hve to read that quite a few times to really understand it. the Techstream you speak of would be the OBDII? But yea my tach and speedometer work fine I did not too long ago after my car was rear ended and i got it back from the body shop had issues with the tach and speedometer. Where they wouldn't calculate properly or even more nor did my odometer calculate the miles I was driving. That also I believe was throwing off the code for the vehicle speed sensor and maybe a few more. Took it to the body shop and they looked into it and said it seemed to be a loose battery cable since when they're working on cars they unhook the battery. But, yea i will look into what you're saying hopefully I can ge it resolved. Also using the OBD I was looking at the summary of diagnosis it did. Everything came up OK or N/A.

Also you said its vehicle speed sensor a is that in the transmission where It woul havve to be taken apart to access it? Because i'm looking online and in my haynes book and I can't find a location for it or what it may look like for the 07.

Thanks for the information and process of how I can go about looking into. I appreciate it.

[Luna2]

Originally Posted by igbeserk

ah thanks for the info man will hve to read that quite a few times to really understand it. the Techstream you speak of would be the OBDII? But yea my tach and speedometer work fine I did not too long ago after my car was rear ended and i got it back from the body shop had issues with the tach and speedometer. Where they wouldn't calculate properly or even more nor did my odometer calculate the miles I was driving. That also I believe was throwing off the code for the vehicle speed sensor and maybe a few more. Took it to the body shop and they looked into it and said it seemed to be a loose battery cable since when they're working on cars they unhook the battery. But, yea i will look into what you're saying hopefully I can ge it resolved. Also using the OBD I was looking at the summary of diagnosis it did. Everything came up OK or N/A.

Also you said its vehicle speed sensor a is that in the transmission where It woul havve to be taken apart to access it? Because i'm looking online and in my haynes book and I can't find a location for it or what it may look like for the 07.

Thanks for the information and process of how I can go about looking into. I appreciate it.

There are 4 speed sensors, 1 for each tire, they go to the skid control ecu, that goes to the VSS drive input a the combination meter for the speedometer. Then the amplified VSS drive output from the combination meter is the source for all other speed monitoring components/ECU's. That speed is compared with the rotational speed from the output shaft (speed sensor a) of the transmission by the transmission computer. If that comparison exceeds the preset value, you will get a fault code... (P0500)

The Techstream is the Toyota diagnostic tool used to read and test the various systems in the car and to clear fault codes through the OBDII connector.

[sgelpel]

so my mechanic replaced the computer and now it seems that the ecm for skid control is fried. He tells me a dealer can install a new one for around $1700. holy crap! I am beginning to wonder if this car is a lemon!! I have never heard of this many problems with a Toyota before. I am thinking about getting rid of it!