Service Engine Light P0803

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Nov 1, 2010 | 01:11 PM

bocallaghan

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From: Houston Texas

Service Engine Light P0803

Ok so I had my system ran and I have P0803 error code (1-4 upshift solenoid circuit). I disconnected the CAGS eliminator under the car and hooked it back up stock. I then had the code erased and it popped back up a few minutes later. I did some digging and found a fuse under the hood that had a transister on top of it. This fuse is supposed to be designated to the transmission and what not. I looked at all my connectors and there doesn't appear to be any corrosion or anything amiss under the car. What could cause this service engine light? Could that fuse be blown? Couldn't tell. Could some other solenoid need changing? Should I buy a new cags eliminator and replace the existing one? Thanks for everyone's help.

Nov 1, 2010 | 01:14 PM

eboggs_jkvl

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From: Jacksonville Florida BWO Dayton, Cincinnati, Bloomsbury NJ, Cincinnati

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You might want to read this for ideas:

http://www.ls2.com/boggs/dtcs/DTC%20P0803.htm

Elmer

Nov 3, 2010 | 08:34 AM

marc8090

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Did you buy the car used? The fuse could have been replaced with a blown smart fuse. It works on some cars, but not all. Do a search, plenty of info on the subject.

Nov 3, 2010 | 08:37 AM

bocallaghan

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I did buy it used. So replacing the blown smart fuse won't fix the problem. I thought I could get a new fuse and a new cags eliminator to see if that would work.

Nov 3, 2010 | 02:28 PM

JoesC5

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First check the resistor in the CAGS eliminator to see if it's open. If so, I think a 2000 ohm resistor is what's in there. If bad, pick up a new resistor at radio Shack and also replace the "smart" fuse with a std fuse.

Nov 3, 2010 | 02:44 PM

eboggs_jkvl

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The ECM is a smart little critter. It not only operates the CAGS solenoid, it looks for the resistance of the coil in the solenoid to insure it's presence in the system. Thus we substitute the resistor to fake the ECM into "seeing" the CAGS solenoid. IF it see no resistance, the SES lights up.

Elmer

Nov 3, 2010 | 03:19 PM

bocallaghan

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From: Houston Texas

ok I'll start by placing a standard fuse under the hood. The resister on the CAGS eliminator looked ok but I will check it again to see if it's bad or needs replacing

thanks!

Nov 4, 2010 | 10:25 AM

bocallaghan

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So I just wanted to thank everyone for their input. Apparently changing the "smart" fuse and replacing it with a standard fuse with the CAGS hookup worked. Again thanks!