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[Help please] Can't enter diagnostic mode

holdensmychoice

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Hello I've got a vn v6 and i've checked for errors many times no probs by bridging the white and black wire with a paperclip, I've just recently put a new clutch in and o2 sensor out of another car because mine was buggered. I also changed memcal to a different 1 and decided i didnt want it anymore so changed it back to original factory 1.... disconnected the negative terminal for 10 mins and reconnected and went for a drive to find the engine light coming on again.. so suspecting its the o2 sensor again i went to bridge how i normally do but now nothing at all is happening... turn the ignition to on and all the usual lights come on as normal but wont enter diagnostic mode. Tried like 5 paper clips and different bits of wire and its definitely not working now. Perhaps the ecu is buggered? is it even possible to maybe put a memcal in backwards? im guessing it isnt and the car probably wouldnt run if it was... any suggestions guys? cheers
 

hi_ryder

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doses the engine light come on when you turn the key into the reds (accessories)? if it dosent the globe is blown and the car wont self diagnosis if this circuit is broken.
 

holdensmychoice

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doses the engine light come on when you turn the key into the reds (accessories)? if it dosent the globe is blown and the car wont self diagnosis if this circuit is broken.
Yeah it comes on as normal along with all the other lights, just for some reason it does nothing now when i put a paper clip into it. tried many times. Would changing the ecu itself help?
 

Not_An_Abba_Fan

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You're obviously putting the paper clip in the correct terminals of the plug? Is the connector pushed hard all the way into the ECU?
 

holdensmychoice

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You're obviously putting the paper clip in the correct terminals of the plug? Is the connector pushed hard all the way into the ECU?

Yeah definitely, i mean ive done this so many times i could almost do it with my eyes closed, i unplugged them and put them back in and made sure they clicked in hard but still no go. I wonder if changing the ecu will solve this problem?
 

Jxfwsf

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try another ecu. or use a long piece of wire and connect the diag mode pin to a good ground on the body of the car and see if that makes a difference
 
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