Hi All. Appreciate any assistance. Car wont start, glow plug light does not light up. Agents replaced 3 and did not attempt the 4th afraid it could break off. Vehicle ran fine for a while. Once again the glow plug light does not light up. If I connect a battery charger, the light comes on immediately and the car starts up. .thanks

 

Then check the battery voltage using the dyno mode or with a multimeter. Should be above, say, 12.2v
What happens if you charge it overnight then disconnect the charger and immediately try to start?

 

Tried that. It starts immediately. After a very short run, the problem returns

 

Looks like you alternator/voltage regulator is toast. What is the voltage when the car is idling vs when driving?
Should be 13.6v and 14.2v respectively.
(Here is how to access dyno mode to check voltage on the go: https://www.google.com/webhp?hl=en#h...w203+dyno+mode)

 

Thanks will test it and post. The agents replaced the alternator and starter 5 months ago

 

Tested battery this weekend 12.8. Used the same battery to start another merc. Checked all fuses and relays. Black relay A 002 542 19 19 circuit won't close. Stopped with another indentical relay, still won't start. I used my finger to close the circuit and the car starts up immediately.

 

It's as though there is not power to the relay to open and close the circut