no glow plug light no engine check light glow plugs not working

[micky22]

my 1997 p38 glow plugs dont work i have no engine check light and no glow plug light it wont start any ideas

 

[dogsbody]

Glow plug relay would be my next port of call.

 

[Datatek]

As above plus the fuse. Has it got a hot start fix?

 

[micky22]

did have but its off now which fuse would it be and would the glow plug relay cause the engine check light no iluminate when the ignition is turned on

 

[paulisa]

on mine one of the plugs had shorted out internally and blew the fuse fitted 6 new ones to be sure and a new fuse and perfect

 

[micky22]

which fuse did it blow?

 

[paulisa]

the big i think 40 or 50 amp one next to the heater plug relay near the fuse box

 

[micky22]

ok thanks will check that

 

[paulisa]

on mine it was just 1 of the plugs maybe good idea to test them before just changing a 2 quid fuse for it to blow again instantly. i tested mine by removing them and putting onto a battery 5 glowed red on the tips the last one just sparked

 

[micky22]

i have read that p38 diesels the glow plug relay is controlled by the ecu not the becm is this true and can it have killed my ecu ?

 

[Datatek]

i have read that p38 diesels the glow plug relay is controlled by the ecu not the becm is this true and can it have killed my ecu ?

Glow plug relay is indeed controlled by the engine ECU. It's unlikely that a faulty relay will have damaged the ECU. The relay and fuse is in the same box as the ECU behind the battery IIRC. Also check the battery feed to the ECU, the wires have been known to corrode inside the plastic sheath.

 

[micky22]

can anyone tell me if i change my ecu and get on with the same numbers on will it comunicate with my becm or will it have to be reprogrammed???

 

[Datatek]

can anyone tell me if i change my ecu and get on with the same numbers on will it comunicate with my becm or will it have to be reprogrammed???

Why would you want to change the ECU? They rarely fail, you are jumping the gun.
A replacement ECU needs to be synced to the BECM and if it were a new one it needs to be set to secure or non secure mode with diagnostics.

 

[micky22]

ok then so if the outer caseing shorted out on the battery would that kill the becm or the ecu ?

 

[micky22]

i had a socket on the nut that hold the wire from the battery to the glow plug relay and touched the ecu caseing would this kill the ecu or becm ?

 

[Datatek]

i had a socket on the nut that hold the wire from the battery to the glow plug relay and touched the ecu caseing would this kill the ecu or becm ?

Sparks never do electronics a lot of good but the casing is earthed so hopefully there will be no damage.
ALWAYS disconnect the battery when working on anything electrical on a P38 or you could render the car uneconomic to repair literally in a flash.

 

[micky22]

yeah i have learnt the hard way

 

[micky22]

so i have checked all fues no have blown could it be the ecu or the glow plug relay which should i do first ?

 

[Datatek]

so i have checked all fues no have blown could it be the ecu or the glow plug relay which should i do first ?

Check the relay first and it's fuse. You really need diagnostics to see if the ECU still functions.

 

[micky22]

ok so its either one of those two not the becm?