Check for 205 ECU Error Codes

How can this help me?

Interrogating the ECU will hopefully point you in the right direction for your fault. If not, at least you'll know what the ECU is doing and what IT thinks is wrong!

When should I do this?

How do I find out if I have any error codes?

Turn the ignition key so that the car doesn't start but powers up the instruments. On the right hand side in the engine bay is a connector marked "diagnostic". Open the protective flap. On the inside of the lid is a diagram showing the location of the pins and a letter identifying them e.g. OX - (Lambda sensor). Locate the TE1 and E1 terminals and connect these together with any old piece of wire or e.g. a paper clip.


Picture coming...
Diagnostic connector location. This is in the same location on all the GT4s Inside the 205 diagnostic connector. TE1 and E1 are highlighted Shorting TE1 & E1 together, any conductor will do e.g. paper clip The engine check light on the dash will flash rhythmically for no errors but will flash a code if the ECU sees a fault condition The CEL looks like this

Note that the ST165 designation is different, these 2 terminals are marked as "T and E1".


How do I interpret the error codes?

Once you have bridged the two terminals together look at the orange engine check light on the dashboard on the right hand side of the steering wheel. This light will flash to indicate any error codes. If this flashes regularly then everything is normal as far as the ECU is concerned. If there is a series of flashes or codes then interpret these as follows:

E.g. for code 54 - 5 flashes, small pause, 4 flashes, longer pause, then 5 flashes, small pause, 4 flashes- this repeats...

*.*.*.*.* .. *.*.*.* ..... *.*.*.*.* .. *.*.*.* .....
5   4   5   4  

* = Dash light on
. = Dash light off, (a slight pause)
Click the above icon to download a video of a code 54, followed by a code 42 error. The video is from a 205, but the clip is also applicable to the 165 and 185

The video is a *.mov file that can be played by a QuickTime Player. Click here to download the free QuickTime player


Error code listing

Code Description What to do?
12 - RPM No G1, G2 or NE signal to ECU, open in G- circuit Starting related, check distributor, starter, ECU. The dizzy is connected to the loom via a plug awkwardly placed under the dizzy - check this, and the dizzy wiring
13 - RPM No "NE" signal to ECU above 1000 rpm Check distributor, ECU
14 - IGN No "IGF" signal to ECU 8 times Check igniter, ignition coil, ECU and IGT wire to igniter. Can be caused by wire feed into the coil. The IGF signal is fed back to the ECU to inform the ECU that the igniter is "ok"
16 - CPU ECU duff Repair or find a new ECU
21 - O2 Detection of oxygen sensor deterioration Check oxygen sensor
22 - WTR Open or short in Water Temp Sensor Check/test Water Temp Sensor and wiring
23 - MAT MAT Fault Check intake air temp sensor connector and functioning correctly
24 - AIR Open or short circuit in Air Intake Temp Sensor Check Air Temp Sensor within intake filter housing
25 - O2 Excessive Lean Air Fuel Ratio Check O2 sensor, fuel system. Replace fuel filter. Check FPR connection and water temp sensor
31 - PIM Open circuit or short in MAP sensor Test or replace MAP sensor
34 - PIM Fuel cut due to excessive turbo pressure Check Wastegate, Wastegate actuator, Wastegate Hose, Turbo Pressure Sensor
41 - TPS Open or short circuit in VTA signal Test Throttle Position Sensor - article
42 - SPD No "SPD" signal over 8 seconds driving Check Vehicle Speed Sensor, SLD (if fitted) and wiring
43 - STA No starter signal over 800 RPM starting Check Ignition Switch
51 - A/C Aircon malfunction Check Throttle Position Sensor - article
52 - KNK Open or short circuit in Knock Sensor Check for broken/brittle wire from KS to ECU, check sensor correctly torqued up, check sensor terminal not covered with oil/shorted out, replace sensor, shake sensor - it shouldn't rattle! There should be no continuity between the centre pin and the body of the KS
53 - KNK Knock control in ECU faulty ECU
54 - INT Intercooler Coolant Low or Pump Failure Top up IC fluid reservoir, test IC water level sensor, test IC water pump. Tip - run car with IC cap removed, blip throttle, watch water level drop, add fluid to max level, swiftly replace cap - this also indicates that the pump runs


Codes from the manual... ...more codes


I have more than one error code! Help!

Multiple error codes will be shown as e.g. 54 then 21, and will then repeat 54 then 21... Some faults bring up more than one error code. Look at what faults are being shown and try to think how they are all connected. Normally only one device has failed/gone weird and that is the cause of the 2 or 3 fault codes.

Yeah okay I think I've fixed it - how do I make the stored fault go away?

Some codes are cleared when you switch the ignition off, others have to be cleared by removing the power to the ECU. This is done by either removing a lead from the battery, (pain in the arse), or simply pulling the 15A ECU fuse located in the engine bay fuse box for 10 seconds ish.


Identify the engine bay fuse box... ...remove the cover to the fuse box in the engine bay... ...under the lid is the layout for the fuses... ...remove the fuse to reset the ECU