mercedes ml 320 cdi w164 no glow plug light no crank

Page may contain affiliate links. Please see terms for details.


New Member
Jan 26, 2019
knaresborough, North Yorkshire
ML 320 w164
Hi to all Im new to this forum and a little unsure if Im posting in the correct place
My car is Mercedes ML 320 3.0 diesel v6 2006 reg at 155000miles . Hoping a Mbr has encountered my problem or knows what the fix could be.
Problem as follows : drove to local shop from cold a distance of 1 mile ,getting back in car turning on all ignition lights came on But without the glow plug light turned key to start and no crank. switched off and re-tried various times with locking and unlocking still no glow light and no crank. i carry the spare key so tried that Ign on :lights on and glow plug light turned to start and car started but cut out within 5 seconds then back to previous scenario, Ign lights no glow and no crank .called AA he could not access any fault codes so assumed it was a EIM problem he recovered me home . Doing a few ignition on offs the glow light would come on crank and start and cut out immediately now sometimes glow light comes on no crank today back to no glow light no crank ,whilst ignition is on i can select using the electronic gear selector N/R/D AND PARK so that works and the electronic steering lock disengages .However i removed the EIM and sent it away to be checked with the keys NO PROBLEMS FOUND . Whilst i wait for it to be returned ive removed the battery and charged with a smart charger initialy it had only showed 12.5 volts and 60% charge . i do not think this is the problem because the car started although cut our 5 secs later one would assume the alternator would immiediatly produce enough amps to top battery up once the engine was running ,one other thing ive noticed over the last few weeks is that from cold if i put seat heaters and heater blower on the engine idle increases to around 1500 from 750 until the engine is warm or the batt is recharged ( but not sure about this ) Does anybody have any ideas please thanks in advance TONY
Needs getting to a MB indy, could be fuel pump relay, but thats just a wild guess.
local MB indy has quoted £350 + vat for full diagnostics plus the cost of a flat bed to recover to them there wont be much change out of £ 800 before i start so indy is out of question
By the way Fuel pump relay runs when ignition is switched on but thanks anyway
Glow plug relay control module? £150 for a Beru from Autodoc?
Not saying it is this, but they are known to be temperamental and fail.

I'm currently wondering if I have an intermittent fault with mine on the OM642 engine.
No fault codes are generated from glow plug relay module failure is common I believe.
local MB indy has quoted £350 + vat for full diagnostics plus the cost of a flat bed to recover to them there wont be much change out of £ 800 before i start so indy is out of question
By the way Fuel pump relay runs when ignition is switched on but thanks anyway
I don't think your indy wants the job with that quote!
That is 5hrs + VAT at current indy rates just to diagnose?

I'd look for another one.
Hi guys i agree he is expensive im waiting for a Icarsoft V3 dedicated Mercedes scanner fingers crossed this will do the trick .Currently checking all the earth ground points any body know where the main engine to chassis earth is located ? trouble is i cannot get under the car as i cannot drive it up onto ramps GRRRRRR
I'm struggling to see the relation between lack of glow plug (light) and crank.
From the description they seem to coincide but I haven't experienced glow plug failure preventing crank, has anyone else?

The only common I can think of the is the engine negative return strap.
That should be visible for inspection from below, toward the rear of the engine. So would need to be jacked onto stands, in this case.
Il check that strap now also when should the fuel pump run ? with ignition on? or only when cranking ? my fuel pump isnt running with ignition on do you know fuel pump relay and fuse location please .the diagram i have show the fuse in rear sam fuse no 30 but this is missing?
also the AA guys scanner would not communicate with the eobd my simple foxwell will not either does eobd have a fuse
Fuel pump should run for perhaps 15 seconds at each ignition cycle. If the ECU fails to see pressure it cuts it. But it should crank and if the fuel pressure is too low it fails to fire.

Again though a lack of negative return means the fuel pump will fail to run. Could be the same cause.

A thought, jump the engine to the negative under bonnet jump terminal with a jump lead for elimination.
Last edited:
Hi guys ive just connected a jump lead from good earth on block to neg jumper point on chassis still no joy, also checked eng earth and that seems to be ok. still getting no fuel pump run when ignition is switched on whats trowing me is that all the info i have says fuel pump fuse should be no 30 in rear sam or fuse box i dont have a fuse in that slot ive put a 40 amp in to see what it does and still the same thing no glow plug light no crank
Update guys found that doing the old wiggle test on the rear fuse box quite hard twisting aswell the glow plug light cam on and engine started letting the twisting pressure of the fuse box stopped the engine so i got it stripped on the bench ill let you know how i get on
  • Like
Reactions: m80
at long last i got a scanner to work on the car the only fault code that is retained is in the rear sam ( 9097) input c 15 .short to ground or open, so now im seaching for the fault any body seen this before

Users who are viewing this thread

Top Bottom