Fiat Ducato 244 - Indicator flashes quickly

Reading time 4 minutes

Updated - February 3, 2025

The blinker on the Fiat Ducato 244 suddenly flashes rapidly. This is a sign that a blinker bulb has failed. So you might think that the bulb has been replaced and that's that.

Murphy has other possible causes in store and so the supposedly defective bulb turns out to be whole. Big question mark: what now?

circuit diagram

Roughly speaking, the turn signal is activated via the turn signal lever on the steering wheel. The blinker relay switches the associated blinker lamps on and off at the legally prescribed rate of 1.5 Hz, corresponding to 90 light signals per minute, as well as the direction indicator in the cockpit.

The electronic control in the relay is designed so that a defined current, analogous to the power of the lamp, must be drawn. If the current is lower, this indicates a bulb failure and the clock frequency doubles.

The flasher relay may also be defective, but this is very rare and is then also noticeable with a complete failure.

Studying the circuit diagram provides information about the connections and which cables (connections) may be the cause:

Here, the left front blinker (F010) has failed. It is supplied with positive via the cable on plug connection 6 of control unit H090 via plug connection B04.

(F011) represents the right front blinker, (F020 / F021) the front side-mounted indicators and (F030 / F031) correspondingly the rear indicators. (E050) are the direction indicators built into the speedometer.

Troubleshooting

Dismantling the control panel

Once you have removed the control panel (two screws at the lower edge of the cover hold the cover to the substructure), remove the white, wide plug from the rear right-hand socket after unlocking the small, centrally arranged retaining lugs, locate the white-pink (SB - bianco rosa) marked cable at connection 6.

Relay check - for safety

Plug another cable with a suitably stripped end into this connection parallel to the cable and wrap the other, equally suitably stripped end around the base of a 21W bulb.

A second cable is connected to a point on the body (earth), the ignition is switched on and the left blinker (in this case) is activated.
The relay now flashes at double frequency. As soon as you connect the earth cable to the free pole at the bottom of the bulb holder, the frequency will correspond to the normal frequency and the bulb will light up in time.

This first proves that the flasher relay actually provides the correct positive voltage at the connection.

cabling

The only remaining causes are the cable connections plus (SB) to the lamp and from the lamp to earth (N - nero).

The Fiat Ducato 244 is known for mass problems after a certain age: Ground connections sometimes seem to go bye-bye due to oxidation. You notice it because "it" sometimes works, sometimes doesn't and at some point fails completely. Exactly like here.

Solution - for plus problem

In rare cases, however, the positive cable (SB) has a cable break. The only thing that helps here is to pull a new cable.

In the partition wall between the engine compartment and the interior, there are several rubber plugs at the top right when viewed from the engine, some of which already serve as cable bushings. Look for the one with the lowest occupancy and thread a (rigid) 1.5 mm² ground wire (yellow-green) through it and push it as far inwards as possible.

Look for it from the inside and pull it up to the center console, where the so-called additional dashboard with the hazard warning switch is located. Tightly wrap a double stranded wire with insulating tape over a length of about 6 cm and pull it from the outside to the blinker.

The turn signal socket and bulb are unlocked from the socket of the turn signal housing with a left turn and removed. Remove the original cable from the socket. The PVC tube surrounding the cable is slit open over about 8 cm. The cables can now be pulled out a little. Shortly after the end of the slit, cut off one of the two cables, the other about 2 cm earlier. The two cable ends in the PVC tube are wrapped tightly with insulating tape to prevent the ends from touching each other. The PVC hose is then also completely secured with insulating tape to prevent moisture from penetrating.

The two ends cut off and stripped to approx. 5 mm with the two cable lugs at the other end of the cable are soldered to the double stranded wire, the ends of which have also been cut off with a 2 cm offset and stripped to approx. 5 mm, so that the cable length is ultimately identical again.

Disconnect the white-pink cable for the left blinker from the above-mentioned connector in the auxiliary dashboard and connect it to the cable of the double stranded wire. It does not matter whether this is the positive or negative wire, as the blinker lamp (not an LED!) works independently of polarity. The cable that is still free is connected to earth, either to an existing earth cable or to the body via a screw connection.

Solution - for mass problem

On the lamp itself, at least on the Flair 7100 on Ducato chassis, there are different colored cables: grey (earth) and grey-red (plus). A second cable (o.75 mm²) is connected in parallel to the gray cable and connected to a new ground point (validate beforehand by measuring!). And then - it flashes again!