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tech 101
tech 101, ASE Certified Technician
Category: Car
Satisfied Customers: 124
Experience:  ase certified till 20010 ir4kv1pe8holif cer id
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2002 hyundai santa fe: Replaced starter and battery..Blows..ECU

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Replaced starter and battery on 2002 hyundai sante fe. Car cranks but does not start. Blows 10 amp ECU fuse. One side of fuse is to ground. Replaced ECU as per suggestion by Hyundai Service Mgr. Did not help. Traced wires from fuse red with orange stripe and brown wires to cruise control. Unpluged cruise control and fuse did not go to ground and did not blow upon cranking engine. Did not start. Pluged cruise control back in. Fuse did not go to ground still would not start. No fuel, no ign. spark. Checked some other plugs on trans, and map. Now fuse blows again. Have crank sensor code, and Mfg, control transmission code. Will not start
have you checked for a faulty ignition switch this is a strong possibility if the problem is intermittent
Customer: replied 8 years ago.
It seems to be intermittent, but it is all surrounded by the ecu, cruise control, crank sensor and Manfucturer transmission. What ever that is. It started with the car not starting. Checked starter it was bad replaced it and battery also because it was old. Car should have started after that but didnt. Was told by the Hyundai Service Mgr. that the ECU probably had gone bad due to a starter spike. The ECU was replaced. I used the actron obdII auto scanner and got the codes mentioned above. Also got os2 code. All of these codes were different everytime I scanned the car. The car set for a few days because of a hurricane here in Fl. and water got under the hood. It dried out for a few days but still didnt start. The starter and battery was done during a down pour and was at first told some ecu's could have gotten wet.
youve got water damage somewhere under the hood if it got that deep remove all connecters for the sensers and all electrical connecters dry then out youll find one is full of water
tech 101, ASE Certified Technician
Category: Car
Satisfied Customers: 124
Experience: ase certified till 20010 ir4kv1pe8holif cer id
tech 101 and 5 other Car Specialists are ready to help you
Customer: replied 8 years ago.
Well thats easy to say and ive checked all that I could find. There seems to me there is one that controls the fuel and Ign, and is powered by that 10 amp ecu fuse. If I knew which ECU that fuse controlled it would be a lot easier. Ive checked most of the manual on line and none show the fuse box or any of the fuses. There are about 5 ecu fuses in the box and only one is grounded. Any Idea which senser it controls? Ive been two days looking for water in a plug or sensor and found none yet.
Customer: replied 8 years ago.
Well thanks for trying. Ill just have to keep looking.

You also could have an issue with the circuit board in the engine compartment fuse box if it got wet. the fuse powers the ECM, cruise module, instrument cluster and the brake light switch. Also CAMSHAFT POSITION SENSOR,MASS AIR FLOW SENSOR,PURGE CONTROL SOLENOID VALVE,CANISTER CLOSE VALVE,IDLE SPEED CONTROL ACTUATOR,EGR SOLENOID VALVE,CRANKSHAFT POSITION SENSOR