My FH-X720BT shows it has no service what does this mean?

check clock spring /horn switch ----horn itself --ground is clean no rust corrosion -

Your going to need a good wiring diagram biy yourself a service manual. Most likely the issue is a bad ground. Take a volt ohm meter check at each bulb socket for 12v. If 12v is present then take a jumper wire and jump the ground wire at the bulb socket to ground if your light works then youve got a bad ground. Good luck

Driveline - Specifications : Volvo Trucks - United Kingdom ...

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Volvo TrucksFind all the driveline specifications for the new Volvo FH, including the engines, I-Shift, ... 12-speed splitter and range gearbox with automated gearchanging system. ... Supplied as standard with I-Shift and gives the gearbox its basic functions. .... Pleasebe aware that if you change your cookie settings, we can no longer ...

[PDF]Volvo FH series Product guide - Volvo Trucks

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Volvo TrucksVOLVO FH AND VOLVO FH16 PRODUCT GUIDE volvo fh series .... You can literally steer the truck with one finger. This not only gives you complete control of the ... By constantly receiving information about vehicle speed, ..... 335 mm under thedifferential. ... Please note: this is not available on a right-hand drive (RHD).

[PDF]Manual New FH - Volvo Group

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AB VolvoIf you have any questions or want to know more about your truck, please contact your. Volvo dealer. ... network across Europe, we can help you with repairs to your truck and its .... Differential lock. .... manual gives you an overview of the .... Adapt the speedand maintain as even a speed as possible. 02. DRIVING TIPS. 16.

My next move would be to check CDI control module.

transmission or manual clutch slip and/or poor driving habits need to be looked at if all else is good.

You might want to look for a vacuum leak on the intake manifold. You also might need to hook up a scope and measure injector duty cycle and compare it with a good cylinder. Also check wiring for chaffing going to the injectors and coil pack. I can provide you with pin out on ECM if you need.

Me too, same problem here.

Have a look at the fuel pressure regulator.

14.6 means your voltage regulator or diode is suspect Despite having new alternator .Ive cross refrenced your smptoms in the haynes workshop manual and alternator is your only end answer.The haynes test is to start vehicle with multi meter connected across the battery terminals,increase the engine speed until the reading remains steady should be approximately 12 to 13v and no more than 14v.switch on as many accessories as possible(headlights heater blower radio etc)check that the alternator maintains the regulated voltage at around 13 to 14v.If the regulated voltage is not as stated then alternator is to be repaired/replaced.Good luck with it and a happy new year.

Be sure to check and see if your wiring to frame ground is good. I am not sure that you "blew" all of this at once. There should be a ground that runs from the light harness to somewhere on the core support. Just be prepared to chase wires. Electrical gremlins are always fun.