DIY nexia tachometer repair

In detail: do-it-yourself Nexia tachometer repair from a real master for the site my.housecope.com.

Hello everyone!
The problem is this: The tachometer lives its own life, it works, then it doesn't.
I shoveled the entire search, both on this site and on others, and did not find anything intelligible. All similar topics are either closed for a long time or without a solution (found an answer and left).
I am already dismantling the torpedo at a time, how to drink tea, only it began to crunch, and the problem can not be localized in any way. I have already been to solder the area where the bolt and the board are connected and smeared with grease and cleaned the contacts on the board. It helps everything for a week, then everything is new. I noticed one discrepancy: When unscrewing the tachometer contact bolts, adhered washers remain on the board (they are soldered or something). Picking them up with a screwdriver, you tear them off, tighten the bolts and everything works.
Also, the work of the tachometer depends on the humidity outside, in the rain it often fails (everything goes to poor contact).
The only thing that helped for a relatively long time, or rather 3 months, was to lubricate the contacts of the board and the bolt with solid oil (three months without worries), but not to disassemble the torpedo every three months.
I found an article on one of the forums where someone mentioned a non-working tachometer & t = 2827 # p44571, but I still did not understand whether they put resistance there because of the difference in the car model or because of a problem like mine.
Can anyone solve this problem. Write how. I am sure that this is not the only one, and that now everyone is closing their eyes.

Help people! What else to try?
This problem really pisses me off! >

The problem is not with him, the cigarette lighter is working fine.

There is no tachometer on the GL Nexia. Some resigned themselves to this shortcoming, but I decided to make up for it and install an external electronic tachometer on the Nexia (16 cl. DOHC GL).

Video (click to play).

Initially, we disassemble the dashboard (see “How to remove the dashboard”).

Also, we are looking for power for the tachometer (“+” and “-“), I took power from the clock. We connect the power, carefully isolate

Next, we are looking for exactly what the tachometer does not work for many. Where to connect the wire for receiving the pulse signal.

Answer: It is connected to the left connector going to the dashboard, to pin "15"

Alternatively, you can install such a tachometer - also a good option! The connection is identical to mine, only the power was taken not from the clock, but from the above left connector of the instrument panel:

"+ 12V" with the ignition on - contact "14"
"Mass" - contact "2"

Daewoo Nexia belongs to the middle class cars. He began his history in 1984. Only then it was called Opel Kadett. When the German manufacturer took the car out of production in 1991, the license for its production was bought by Daewoo Motors. The car went through a deep restyling and in 1994 appeared on the South Korean market under the name Daewoo Racer, and a little later began to be sold around the world as Daewoo Nexia. It was discontinued in South Korea in 1997, but production continued in Vietnam, Egypt, Romania and Uzbekistan. Moreover, in the last of the above countries, the production of the car continues today.

At different times, various engines were installed on the car. In total, during the production of the car, four different types of engine were provided for it - their indexes F16D3, A15SMS, A15MF, and also G15mMF.

Based on the type of motors used, various speedometers were installed on the cars. For A15MF, G15mMF engines, a mechanically driven speedometer was used, which was equipped with a special cable. On more modern engines F16D3 and A15SMS, data on vehicle speed was transmitted to the device from a speed sensor.

However, in both the first and second options, there are some design flaws that can appear during long-term operation of the car and cause a malfunction.

Depending on the type of drive, each type of Daewoo Nexia speedometer has its own malfunctions.

For a speedometer with a cable drive, the main malfunction is the destruction of the cable ends, made of plastic and having the shape of a tetrahedron. During operation, their edges are erased and cease to transmit torque to the speedometer.

In order to confirm or deny this malfunction, it is imperative to dismantle the instrument panel. After that, it is necessary to unscrew the union nut, with which the cable is attached to the speedometer, which, in turn, makes it possible to assess the condition of the cable tip. If the tip is in good condition on the side of the instrument panel, the only option for checking is to drive a certain distance - approximately 5-6 meters, while holding the speedometer cable with your hand.

Removing the instrument panel on Daewoo Nexia

If the torque is not transmitted from the gearbox to the cable, it means that the tip has failed on the other side.

In this case, it is necessary to perform the following actions - open the hood and unscrew the union nut, with the help of which the cable is attached directly to the gearbox, which serves as a conductor, with the help of which the torque generated on the secondary shaft of the gearbox is taken off. This part is located in a hard-to-reach place, since the tanks of the cooling system and the hydraulic booster are closely located nearby, which will need to be dismantled.

In this place, there may be one of the following malfunctions - the teeth of the plastic gear of the reducer were cut off, wear or destruction of the cable tip, a loose union nut that fixes the cable.

Newer Daewoo Nexia, equipped with F16D3 and A15SMS engines, are equipped with an electronic speedometer. To obtain information about the speed of the vehicle, the data that is transmitted to it comes from a special speed sensor. Its work is reduced to the transmission in real time of information about the frequency of rotation of the gearbox shaft, which is processed by the electronic control unit.

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E37 Oil pressure drop indicator

E38 Engine system malfunction indicator

E39 Indicator for the parking brake and the drop in the brake fluid level

E40 High beam indicator

E41 Washer fluid level drop indicator

E42 Turn signal indicator

E43 Signaling door open

E44 Seat belt not fastened warning lamp

E46 Dashboard illumination lamp

H9 Fuel level indicator

Zh1 Coolant temperature gauge

R5 Fuel level sensor in the tank

R6 Coolant temperature sensor

R7 Window washer fluid level indicator switch

S43 Switch (4-speed automatic transmission)

Air conditioner, electric fan, blower

F48 Air conditioner switch illumination lamps

K21 Electric fan relay (high speed)

K22 Electric fan relay (low speed)

K23 Air conditioning compressor relay

K24 Blower motor relay

K25 Electric motor (optional)

M26 Electric motor

M27 Blower motor

R10 Blower motor resistor

R11 Fan motor resistor (low speed)

532 Fan switch

533 Radiator temperature relay

534 Low pressure switch

535 high pressure switch

536 air conditioner switch

Y1 Air conditioning compressor

Y10 Solenoid for recirculation mode activation.

The tachometer is an important part of the car that measures the number of revolutions of the engine. This device allows you to monitor that their number is not critical, which can lead to engine malfunction and the need for expensive repairs. When the tachometer does not work, it confuses most drivers.

In order to fix the problem, you must first determine its cause. The method of repair will depend on this.

There may be several reasons:

Breakage of the LED screen (if the tachometer is electronic). With prolonged use, the device breaks down and its operation cannot be restored. This problem is solved by replacing the display.
Faulty wiring, deterioration of contacts, which entails the loss of the source of impulses from the motor to the device. To determine such a breakdown, you should inspect the electrical wires. If you see small cracks, they need to be soldered. In case of serious breaks, the wiring needs to be replaced.
The engine speed sensor is out of order. In this case, the tachometer needle jumps from side to side. In most cases, it is sufficient to replace the part to make the tachometer work again.

The video shows signs of a faulty tachometer:

The reasons listed above are the most common, and their elimination allows the mechanism to return to work.If after the inspection you could not find anything, we recommend that you drive the car to a service center. Experts will be able to identify the problem and fix it. You may need to replace a regular unit, which is quite realistic to do yourself.Before connecting the tachometer to the engine, you need to consult a specialist whether the device is suitable for your car model. Install it on or near the dashboard. The black terminal (minus) must be connected to the body. Red (plus) should be connected to the terminal of the ignition switch with a voltage of 12 V. The device input wire is connected to the terminal of the switch or the breaker of the distributor (depending on the type of ignition system). If a backlight is provided, connect its wire to the size switch.The video shows how to repair a tachometer with your own hands:

Removing the instrument panel on Daewoo Nexia

If the torque is not transmitted from the gearbox to the cable, it means that the tip has failed on the other side.

Newer Daewoo Nexia, equipped with F16D3 and A15SMS engines, are equipped with an electronic speedometer. To obtain information about the speed of the vehicle, the data that is transmitted to it comes from a special speed sensor.Its work is reduced to the transmission in real time of information about the frequency of rotation of the gearbox shaft, which is processed by the electronic control unit.

Daewoo Nexia speed sensor

As a result of the modernization, the durability of the Daewoo Nexia speedometer has improved. However, mechanical damage was replaced by electronics problems. A typical malfunction for these models is the malfunction of the speed sensor, which occurs due to its depressurization and subsequent ingress of liquid into the interior.

I wrote a little incomprehensibly, what is repeated after a while?
I understood like this:
The machine works fine, suddenly the check comes on and the tachometer stops working.
After a while, the check goes out and the tachometer starts to work - So?

smr 07 Mar 2012

You understood everything correctly. I have an Auto-Askan scanner.

aleksein 08 Mar 2012

And when the check lights up and the tachometer stops working, how does the engine behave? And more - it stops working tachometer only, or all the devices in bulk?
Honestly, I don't remember exactly where the signal to the tachometer is coming from on Naxia, but there can be only two options - either from the coil or from the ECU. If from a coil, then this should immediately somehow affect the operation of the engine; if with an ECU - there may be a malfunction periodically occurs in the ECU itself.

OK. From the ignition coil. As far as I remember, there is a "cadet" system - the switch is located inside the trombler, and in the same place - the master inductive generator. If the tachometer does not work, there may be at least three options - switch malfunction, ignition coil malfunction, wiring malfunction. The only question now is how to filter one from the other.

What coils, what system is the machine full injector.

They made fun. It's good that at least not a complete bike)))
There is a single-coil system. Whether it is an injector or not an injector, the mixture in the cylinder must somehow ignite. Therefore, you cannot do without an ignition system.
And I am personally embarrassed by the fact that “the check is on, but there are no errors on the scanner”. If it is on, there should be any errors, it is not for nothing that it is on - it signals to you that something is wrong. It is on these errors, in principle, that the diagnosis depends. Therefore, you should probably go to a normal diagnostician who can read the errors on this car.