When i switch my dewalt de9118 changer on with no battery the LED flashes red once and the voltage on the output terminals is 125 V dc. Is this correct, if not, any suggestions

Sound like one of the Capacitors on the Power Supply has blown.

If it's the same on both AC & DC then its probably on the output of the transformer.

If you can open it up and post pictures or see if one has a buldge in the top or liquid leaking out.

The flashing light indicates the charger is charging the battery (or attempting it) and if it never finishes charging you should try to charge a different battery, if the charger charges that one ok then the battery is bad.

Disconnect the - lead from that battery, Repower the charger. The LED should be green. If it stays RED, charger defective.
Reconnect the - lead to the battery, measure voltage when charger is on. Should be between 11.5 and 13 volts. If OK, replace the battery. If lower than 11.5, check for charger cable connections OR for a connected load ( power drawing ) of more than 10 amps.

check : H-output tangester / EHT output voltage line 12v /24v 180v check dyiod /capaciter / ragistance ..
if your tv set red led is cantinu on then standby tr.checked if ok then
cheked 5v ragulater ic or prosasor cristl and with canecting pf


1.open s.by tr. check pin voltage
if ok
then check EHT output section h-driver transfermor h-puls 2.1v ac
if not then check croma ic input voltage B+ is 8 v dc and canacting spaer.

Get a battery check first and have it charged. Then, switch off all lights, radio, ignition switch. Reconnect the charged battery negative ground first, then, the positive terminal. Find if there's a spark. if it does, then, you must check your electrical wiring since this is grounded. Do not connect the positive terminal. Clear the grounded connection first. If no spark, go ahead. Crank your engine, and let it run at neutral position. And check the voltage that goes out of the alternator, this must be more than 15 volts DC. Then check the voltage output of the regulator which must be 13
to 14 volts DC. However, if you cannot get the right voltage at the
alternator., you have to replace it. Then, you can check the regu-
lator output voltage, and get the right voltage. Get this done,. and
send your e-mail for the result.

The battery has probably lost it's ability to receive a charge. Is it old? Check the output of charger, should be around 26 volts DC at the output jack.

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when charger is plug in to ac it will blink once.normal voltage out for the unit in between 36v to 55 volt. the reading u have is normal.