Quite a bugger

The problem is that the front bumper and the wing signal lights are not working.
Checked the fuses, bulbs and front lamp relay module. I also switched the front lamp modules side to side, but did not work.
Actually there is no clicking sound from the relay module (front lights are ok), so the problem must be somewhere deeper. The rear left signal light is ok.
So - whereto now?
Inspecting the wiring diagrams I noticed that there is a diode in one lead, where could that be found?
I'll try to jiggle the connectors from the main control unit and check the ground connections tomorrow, though they seemed to be fine.

Any suggestions?

 

Check your grounds,and also use a test light to see if you have enough amperage getting to the bulp assy.

 

Hi Heimis,

I agree with Lumppy47. The test light (tl) is your friend.

You may already know this, but if not read on.

Test the tl. Hook the alligator clamp of the tl to the +tive battery terminal. Touch the engine block or other good ground with the tl's probe - it must light. If not, you got a bad tl bulb or a bad tl.

Pull the front turn signal bulb out of its socket, hook the alligator clamp of the tl to the -tive battery terminal, turn on the ignition key and your turn signal switch and probe the empty socket for the power terminal. If you have power, the lamp may even blink. If you don't, you have a power lead problem.

If you have power, turn off all switches, and hook the alligator clamp of the tl to the +tive battery terminal. Now, touch the tl's probe onto the casing of the empty socket. tl should light up if the ground is good. If not repair the ground.

Here's a generic troubleshooting flow chart for turn signals:

TROUBLESHOOTING BASIC TURN SIGNAL AND FLASHER PROBLEMS

Best of Luck

 

Hi all

I don't have a test light, but did some testing with a voltage meter instead
And the problem is, that there is no clicking sound from the lamp module. It reacts to taking off the bulbs, so the failure part is working.

The ground connections are ok, the wires in the wing are ok, the wires that can be seen under the dash are ok. So, that would leave the ecu, but the rear left signal is just fine. And the wiring from the ecu to the front and rear lamp modules comes from the same spot (according to diagrams).

I didn't have a suitable wire to test if the system works adding an other straight connection from the ecu to the lamp module. Nothing much left to be tested...

 

OK, we're now using a digital voltmeter - it is safer to use on these electronic systems.

One of the following tests should fail.

After you disconnect the Left Front Relay and Bulb Failure Module (LFR-BFM)

1. do you get +12V at the Brn/Grn wire?
2. do you read 0 Ω (ohms) between the Blk/Pnk wire and ground?
3. if you apply +12V to the Grn wire, does the turn signal lamp light up?

Further,

if you reconnect the LFR-BFM and disconnect the Central MicroProcessor (CMP) connector, do you read 0 Ω (ohms) between the CMP connector's Pnk/Yel wire and ground?

Finally,

if you again disconnect the LFR-BFM connector, keeping the CMP connector disconnected, do you read 0 Ω (ohms) along the Yel/Gry wire from the CMP to the LFR-BFM end?

 

At first I didn't test the bulb-end wires, because I thought that the LFR-BFM wasn't getting a signal at all.
Now when I tested the wires on that end, the signal lights did not light up when applying +12V to the green wire. I'll try re-wiring them.

 

For those reading and wish to follow the fun, here's the circuit found in Hayne's:

 

Did the rewiring, and the lights lit when given +12V. Still the signals don't work though. Next: CMP and stuff.

 

OK...

No signal thru the yel/gry -> snatched a new wire parallel to that.
Still no action.
Bypassed the BFM connector -> works just fine \o/

Quite a trouble to find a lo-tech problem, as it often turns out

Thanks for the troubleshooting.
All the wires specified can be found from the diagram, you just have to trust that they are after all made as specified