engine management warning lamp

[paul-g]

hi  all i have an espace 2.oltr j636 1993 j7r engine
the mil warning lamp does not work at all, i looked at a wiring diag on autodata and checked on the car, the lamp appears to be wired back down to the diagnostic connector and from there to the ecu there are four wires at this connector, live, ground, and two white wires, one to the ecu and one to the mil,  there is a dotted line on the diagram abridging the two white wires, my question is should there be a bridge fitted here, if i put a wire across the two the mil lamp works but stays on with engine running, can some one tell me if i am on the right track as assuming this is right i have a fault warning, i put a snap on scanner on the car which showed no faults, also the ecu has recently been repaired by a specialist due to a high idle speed fault and new idle control valve fitted as well. the car runs ok apart from slight hesitation from cold which can be driven through, cheers P

[espaceman]

Any scanner for diagnostics should be able to tell you the MIL status (warning light) as seen by the computer on the vehicle (ECU). YOu need to establish that the MIL is illuminated when ignition is on -engine not running & OFF when engine running. 

It this the case when you say "no faults "

[paul-g]

Hi yes the scanner showed no faults with engine running, if i bridge the two wires the mil light will activate with ign on and will stay lit with engine runnning, so i guess that there should be a bridge in the diag socket, and a need to have it scanned again?
regards Paul. 

[espaceman]

Hi Paul,
From memory I remember that the cap or cover on the Renault Diag socket has a bridge.  Its purpose(depending on model) was to provide a circuit to the MIL light. It had to be in the closed position.

Is the diag socket ok including the cover. If not or if its missing the MIL will not come on which may explain why you do not see any light on in the dash. There may still be a fault.

When the vehicle was scanned did you look at the data on the scanner and happen to notice the following " MIL STATUS ...... ON" ? or " MIL STATUS.........OFF" If "ON"  there is a diagnostic fault even though the MIL is not illuminated

Espaceman

[paul-g]

Hi Espaceman, the cap is ok but there is no bridge, i did not check the mil status as suggested, i'll have to see if i can borrow the scan tool again and check it again as if i put a wire in the socket instead of the bridge the light stays on with the engine running. cheers for the response, regards Paul.