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My son's 97 Camry had a check engine light on and the mechanic replaced the transmission neutral safety switch. The light came on again after 2 days. The mechanic now says the bad switch probably messed up the computer and it has to be reprogrammed or updated. If that doesn't work, it will have to have a new computer. He says there is continuity between the computer and switch. The code is P1780.

Having spent just over $400 so far, the cost of updating the computer ($2-300)seems stiff. I know what a new computer costs, I just want to know if all this seems reasonable.
 

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there is no reason to replace a Toyota ECU, more than likely you have a bad ground somewhere or the code is a result of something else. You need to take it to someone who will not charge you to pull the code and read the possible causes (most auto parts stores will do this for free), then think about spending more money on the problem. It could end up a lot cheaper than just replacing parts.
 

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My son's 97 Camry had a check engine light on and the mechanic replaced the transmission neutral safety switch. The light came on again after 2 days. The mechanic now says the bad switch probably messed up the computer and it has to be reprogrammed or updated. If that doesn't work, it will have to have a new computer. He says there is continuity between the computer and switch. The code is P1780.

Having spent just over $400 so far, the cost of updating the computer ($2-300)seems stiff. I know what a new computer costs, I just want to know if all this seems reasonable.
It is possible this is true.
It's either a short in the neutral safety switch circuit. A bad neutral safety switch or a bad ecm .
 

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Nine times out of ten that code is set due to a pinched or broken wire going from the neutral safety switch to the rear tail lights/back up lights. Check the wiring harness in the trunk where it flexes when you pop the trunk open. I bet you'll find at least 1 damaged wire. Reprogramming the ECM will not fix anything.
 

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Discussion Starter #6
You are absolutely right! Thanbk you. A broken ground wire fixed the problem. Now, what do I do about the mechanic and the sunk costs--probably nothing....
 

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Put it behind you and make sure it never happens again. Money is time, and you can't get either back. These message boards are usually 24/7 so come back if you ever feel like you are being pushed around by a mechanic :)
 

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Turned out to be some broken wires near the trunk loom like usual. Spliced them with some wires hanging so there's a bit of slack when the trunk is extende. Hope the smaller gauge keeps working!
 

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Turned out to be some broken wires near the trunk loom like usual. Spliced them with some wires hanging so there's a bit of slack when the trunk is extende. Hope the smaller gauge keeps working!
I would get a spool of the same gage wire and splice that in. Using smaller gage wiring than the system was designed for is just not worth the risk, IMHO. A bit of the correct gage wiring is cheap insurance.

Mike
 

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Turned out to be some broken wires near the trunk loom like usual. Spliced them with some wires hanging so there's a bit of slack when the trunk is extende. Hope the smaller gauge keeps working!

How did you find the broken wire? was it obvious? Was the wire in the group by the back hinge?

I am getting the same code. For years I have had problems with back tale lights. The only error I would receive was the lights warning on the dash. Now I am getting the check engine light too.
 

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"The only error I would receive was the lights warning on the dash. Now I am getting the check engine light too."

These two things may or may not be related. Get the code(s) read. If your car is a 96 or newer, it is OBD2 and you can get the code read for free at Autozone, along with other parts stores. If you don't have Autozone in your area, make a few phone calls to other auto parts stores in your area and ask if they offer this free service. Then post back here with the code(s) and someone should be able to give you some direction. If your's is a different code, I would suggest starting your own thread with a proper title based on the code.

Good luck.

Mike
 

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97 camery P1780

I added to the old post because it is quite revelent to my problem. I am receiving code P1780 which is the Park/Neutral position switch.

I played with the wires last night. I could not see anything - just wiggled them arround. This morning the check engine light is off. However, the "lights" warning on the dash is still on.
 

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Check engine p1780,rear light indicator

Toyota camry 2000. In the morning the Rear Light Failure Indicator came on and soon after the check engine turned on on the dash.
At this time when i press brake pedal ,the 'R' sqaure light blinks on dash even if i am in '

I went to the mechanic he said the code is p1780 and he has replace some brake light chip in the left side of trunk and he has to replace park/Neutral switch under the hood.
Is that the correct diagnosis?..Should i repair it immediately or i can wait for 1/2 weeks?
 

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Broken trunk lid harness, P1780

I have 2001 Camry.
Found 4 broken wires in the harness following up the trunk lid.
Symptoms were:
"Light Failure" warning lamp on instrument panel
"R" shift indicator being on always, in addition to "D", "N", etc
Check Engine warning lamp - OBD code P1780
All trunk mounted lamps not working - Stop, Tail, Back up, License plate

See related links:
http://repairpal.com/tail-light-relay-box-531#
http://www.toyotanation.com/forum/showthread.php?t=113173
http://camryforums.com/forum/archive/index.php/t-2962.html
http://www.automotivehelper.com/topic128166.htm
 

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Had similar problem on a 2000 Camry LE. Rear light warning came on and noticed both backup lights were blown. Fixed that then shortly after the check engine light was on with a code of P1780 read with a obdII reader. Also had the reverse "R" indicator on the dash come on each time I pressed the brake pedal.:headbang:

I found the broken wire. It is a white wire with a black runner. It was located in the wire bundle running down the left hinge of the trunk lid. The break was about three inches before it joined a larger wire bundle in the left quarter panel. The wire bundle bends each time you open and close the trunk and becomes stressed and kinked. This white wire has the largest gauge of all the wires and probably has a more brittle outer layer. The rest of the wires looked OK. I spliced in a 2 inch piece and no more problems. Removed the check engine warning with the obdII code reader I purchased from Harbor Freight. I relieved some stress in the wire so hopefully it won't happen again.

People who have similar symtoms need to check the trunk wiring before chasing a dead end and spending a lot of money on a neutral safety switch. I almost purchased one before doing a little more reseach here.

Total cost to fix. $45 for the code reader and some spare wire, wire shrink wrap, solder and soldering iron I already had.

Thanks everyone.
-Scott
 

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P1780

Nine times out of ten that code is set due to a pinched or broken wire going from the neutral safety switch to the rear tail lights/back up lights. Check the wiring harness in the trunk where it flexes when you pop the trunk open. I bet you'll find at least 1 damaged wire. Reprogramming the ECM will not fix anything.
Thanks.. Fixing the broken wire going from the neutral safety switch to the rear tail lights/back up lights worked for my car
 
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