Instruments - Revision history

Grrrmachine at 13:11, 4 August 2013

2013-08-04T13:11:08Z

Grrrmachine at 18:40, 13 May 2013

2013-05-13T18:40:20Z

Grrrmachine at 08:34, 20 April 2013

2013-04-20T08:34:32Z

Grrrmachine at 07:19, 8 October 2012

2012-10-08T07:19:18Z

Grrrmachine at 07:15, 8 October 2012

2012-10-08T07:15:34Z

Grrrmachine at 13:29, 29 September 2012

2012-09-29T13:29:53Z

Grrrmachine at 13:27, 29 September 2012

2012-09-29T13:27:04Z

Grrrmachine at 13:24, 29 September 2012

2012-09-29T13:24:54Z

Grrrmachine at 13:17, 29 September 2012

2012-09-29T13:17:14Z

Grrrmachine at 19:15, 12 September 2012

2012-09-12T19:15:29Z

@@ Line 164: / Line 164: @@
 ==Rev Counter Not Working==
-The rev counter takes its signal directly from the [[ECU]]. It's a square-wave signal, so you can't check it with a regular multimeter, but you can check that the signal wire is in good condition between the clocks and the ECU. This is a black wire that, on Motronic 1.3 vehicles, runs from [[ECU_Pinouts#Motronic_1.3|ECU pin 6]] through the [[C101]] plug pin 7 to the dash cluster's blue plug pin 7. Most likely, there is corrosion on the C101 plug which is affecting the signal.
+When your rev counter starts playing about, it's one of the key symptoms of failing [[Instruments#SI_Batteries|SI batteries]]. The giveaway will be that you can't reset your service lights either, so don't start hunting for wiring issues straight away.
 For older vehicles, especially those using [[Jetronic]], there is a secondary plug next to the ECU which carries the tachometer signal to the instruments known as C104.

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 ==Temp Gauge Not Working==
-The [[Instruments#Temp_Gauge|Temp Gauge]] is driven by the Brown Plug, a heat resistor that screws into the engine head. Failure of the brown plug is rare, but not uncommon. To test, first unplug the cable from the brown plug, and earth the terminal with a piece of wire (for older cars with two-pin terminals, just bridge them together). If you switch the ignition on, the gauge should go to full hot. If it doesn't, reconnect the cable and repeat the test by earthing pin 4 (brown/purple wire) of the [[C101]] plug. If it now works, the issue is normally corrosion of the [[C191]] plug.
+The [[Instruments#Temp_Gauge|Temp Gauge]] is driven by the Brown Plug, a heat resistor that screws into the engine head. Failure of the brown plug is rare, so it's best to first test at the [[C101]] plug to determine whether the fault is in the engine bay or the instrument cluster. To test, first unplug the C101 and earth pin 4 (brown/purple wire). Now if you switch the ignition on, the gauge should go to full hot. If it does, repeat the test at the brown plug by removing the cable from the brown plug, and earthing the terminal with a piece of wire (for older cars with two-pin terminals, just bridge them together).  If it now works, the issue is normally corrosion of the [[C191]] plug.
-If the wire test at the C101 plug still doesn't make the gauge move, the most common cause of temperature gauge issues is the Brass Nut; a small nut at the back of the dash cluster that comes loose over time. Simple tightening of this nut can resolve a number of issues, but access to this nut requires the dash cluster to be removed, which is why testing the wiring with the above method is often the preferred solution.
+If the wire test at the C101 plug doesn't make the gauge move, the most common cause of temperature gauge issues is the Brass Nut; a small nut at the back of the dash cluster that comes loose over time. Simple tightening of this nut can resolve a number of issues, but access to this nut requires the dash cluster to be removed, which is why testing the wiring with the above method is often the preferred solution.
 If you have your dash cluster removed, it is also worth investigating the condition of the [[Instruments#SI_Batteries|SI batteries]], the [[Instruments#Brake_Pad_Light_Flickering|brake pad resistor]], as well as the brass nut on the back of the [[Instruments#Fuel_Gauge_Not_Working|fuel gauge]].

@@ Line 67: / Line 67: @@
 The large right-hand gauge is the Tachometer. On lower-specification cars, this was replaced with a clock.
-The tachometer is arguably the most problematic instrument in the dash cluster, and the source of 90% of dash problems. Most of these issues can be traced to the [[Instruments#SI_Batteries|SI batteries]].
+The tachometer is fed by a signal from the [[ECU]]. This black wire goes through the [[C101]] plug to the instrument cluster, and goes to pin 7 of the blue plug (C1). However, on older vehicles (earlier than 1987) the simpler engine management system provided tachometer and fuel rate data through a separate plug, not the main loom.
-However, on older vehicles (earlier than 1987) the simpler engine management system provided tachometer and fuel rate data through a separate plug, not the main loom. If your pre-facelift car has Tachometer issues, try to locate the small three pin plug and socket above the pedal area, and ensure that it is connected properly.
+The tachometer is arguably the most problematic instrument in the dash cluster, and the source of 90% of dash problems. Most of these issues can be traced to the [[Instruments#SI_Batteries|SI batteries]]. If your pre-facelift car has Tachometer issues, try to locate the small three pin plug and socket above the pedal area, and ensure that it is connected properly.
 If you have swapped your pre-facelift engine to a facelift, and find that your tachometer no longer works, this plug is the issue.  Your new engine loom feeds the signals that went through this connector via the 20 pin C101 engine loom plug, so you have the choice of either extending two wires from the hanging plug to the engine loom socket next to the fusebox (as they are in later body looms), or teasing the two wires out of the engine loom, near the ECU plug, cutting them (abandoning the rest of the wire to the C101 plug) and splicing the plug from your old engine loom onto the wires.

@@ Line 33: / Line 33: @@
 ==Speedometer==
-The Speedometer tells you how fast your car is going.
+The Speedometer tells you how fast your car is going. It takes this measurement from a sensor inside the [[Differential|differential]], which means that the displayed speed is dependent on the size of [[Wheels|wheel]] and [[Tyres|tyre]] you are using.
-The speedometer takes its reading from a pulse generator in the [[Differential|differential]]. This is a very simple sensor and very rarely breaks; however the plug from the sensor is exposed to the road, and the wires very often corrode and break. If your speedo isn't working, cut off the plug and 30cm of wire from the differential sensor, and replace.
+E30 speedometers are calibrated to display a higher-than-actual speed, which was common among manufacturers at the time.
-The speedometer is also powered by [[Fuse_Box|Fuse 12]], through a red/green wire which also serves the [[E30_ICE|stereo]]. If you have worked on your stereo recently and are now having speedo problems, check this wire.
+If your speedometer has stopped working, [[Instruments#Speedo_Not_Working|click here]].
 [[Cruise_Control|Cruise control]] systems require speed information to work properly. A green plug connects to the back of the dash cluster with provides additional pins to which the cruise control can be connected.
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 ==Speedo Not Working==
 ==Rev Counter Not Working==

←Older revision		Revision as of 07:15, 8 October 2012
Line 159:		Line 159:

	==Rev Counter Not Working==		==Rev Counter Not Working==
		+
		+	The rev counter takes its signal directly from the [[ECU]]. It's a square-wave signal, so you can't check it with a regular multimeter, but you can check that the signal wire is in good condition between the clocks and the ECU. This is a black wire that, on Motronic 1.3 vehicles, runs from [[ECU_Pinouts#Motronic_1.3\|ECU pin 6]] through the [[C101]] plug pin 7 to the dash cluster's blue plug pin 7. Most likely, there is corrosion on the C101 plug which is affecting the signal.
		+
		+	For older vehicles, especially those using [[Jetronic]], there is a secondary plug next to the ECU which carries the tachometer signal to the instruments known as C104.

	==Fuel Gauge Not Working==		==Fuel Gauge Not Working==

@@ Line 181: / Line 181: @@
 A little bit of fresh solder and the application of a hot soldering iron, and the job's done.
 [[Category: Technical]]
 [[Category: Electrics]]
 [[Category: Interior]]

@@ Line 99: / Line 99: @@
 ===Brake Lights===
-For those cars fitted with brake pad sensors, a [[Brake_Pad_Sensor_Light|flickering light]] is a known issue.
+For those cars fitted with brake pad sensors, a [[Instruments#Brake_Pad_Light_Flickering|flickering light]] is a known issue.
 ===Indicators===
@@ Line 175: / Line 175: @@
 ==Brake Pad Light Flickering==
+[[Image:220ohm_resistor.jpg|thumb|right|140px|Brake pad resistor joints]]
 A very common issue relates to the Brake Pad Wear indicator, which has been known to flicker or come on at random intervals, regardless of the condition of the brake pads themselves. This problem is caused almost exclusively by a loose resistor within the dash cluster.

@@ Line 53: / Line 53: @@
 Fuel gauges can be identified by a label on the side of the gauge.
-Fuel gauge problems are very rarely related to the gauge itself, and are far more likely to be caused by faulty fuel senders. Learn more about the [[Fuel#Fuel_Level_Senders|fuel level senders]].
+If your fuel gauge isn't working, [[Instruments#Fuel_Gauge_Not_Working|click here]].
 ==Temp Gauge==
@@ Line 161: / Line 161: @@
 ==Fuel Gauge Not Working==
 ==Temp Gauge Not Working==
-The [[Instruments#Temp_Gauge|Temp Gauge]] is driven by the Brown Plug, a heat resistor that screws into the engine head. Failure of the brown plug is rare, but not uncommon. To test, first unplug the cable from the brown plug, and join the two terminals with a piece of wire. If you switch the ignition on, the gauge should go to full hot. If it doesn't, reconnect the cable and repeat the test by earthing pin 4 (brown/purple wire) of the [[C101]] plug. If it now works, the issue is normally corrosion of the [[C191]] plug.
+The [[Instruments#Temp_Gauge|Temp Gauge]] is driven by the Brown Plug, a heat resistor that screws into the engine head. Failure of the brown plug is rare, but not uncommon. To test, first unplug the cable from the brown plug, and earth the terminal with a piece of wire (for older cars with two-pin terminals, just bridge them together). If you switch the ignition on, the gauge should go to full hot. If it doesn't, reconnect the cable and repeat the test by earthing pin 4 (brown/purple wire) of the [[C101]] plug. If it now works, the issue is normally corrosion of the [[C191]] plug.
-If the wire test at the C101 plug still doesn't make the gauge move, the most common cause of temperature gauge issues is the Brass Nut; a small nut at the back of the dash cluster that comes loose over time. Simple tightening of this nut can resolve a number of issues, but access to this nut requires the dash cluster to be removed, which is why testing the wiring with the above method first is the preferred solution.
+If you have your dash cluster removed, it is also worth investigating the condition of the [[Instruments#SI_Batteries|SI batteries]] as well as the brass nut on the back of the [[Instruments#Fuel_Gauge_Not_Working|fuel gauge]].
 [[Category: Technical]]
 [[Category: Electrics]]
 [[Category: Interior]]

←Older revision		Revision as of 19:15, 12 September 2012
Line 27:		Line 27:
	Inside each dash cluster is a coding plug, which is specific to each engine, be it a [[Engines\|4-cylinder or 6-cylinder]] unit. When replacing your dash cluster with that from a different model, it is an incorrect coding plug that causes instrument problems.		Inside each dash cluster is a coding plug, which is specific to each engine, be it a [[Engines\|4-cylinder or 6-cylinder]] unit. When replacing your dash cluster with that from a different model, it is an incorrect coding plug that causes instrument problems.

		+	The coding plug can be accessed by removing the plastic trim around the instrument cluster; the cluster itself does not need to be removed.

	=Individual Gauges=		=Individual Gauges=