Check for 165 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 T and E1 terminals and connect these together with any old piece of wire, or e.g. a paper clip.


Diagnostic connector location, in the same location on the 185 and 205 Inside the 165 diagnostic connector Shorting T & E1 together, 165 diagnostic port shown 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 ST185 and ST205 designate these 2 terminals as "TE1 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?
11 - ECU Momentary interrupt in power to ECU Check relays, ignition switch, ECU
12 - RPM No "NE" or "G" signal to ECU for 2 sec after engine cranked 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 8-11 times Check igniter, ignition coil, ECU. 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"
21 - O2 Detection of oxygen sensor deterioration Check oxygen sensor and wiring
21 - O2 Open or short circuit in O2 sensor heater Check oxygen sensor and wiring
22 - WTR Open or short in Water Temp Sensor Check/test Water Temp Sensor and connector
24 - AIR Open or short circuit in Air Temp Sensor Check Air Temp Sensor. Located within AFM for 165/185 and air intake box for 205
25 - O2 Excessive Lean Air Fuel Ratio Check O2 sensor, fuel system, AFM. Replace fuel filter. Check FPR connection
26 - O2 Excessive Rich Air Fuel Ratio Check O2 sensor and fuel system, AFM, FPR
31 - AFM Open circuit or short in VC signal Test or replace Air Flow Meter - article
32 - AFM Open circuit or short in E2 signal Test or replace Air Flow Meter - article
34 - TRB Fuel cut due to excessive turbo pressure Check Wastegate, Wastegate actuator, Wastegate Hoses, Turbo Pressure Sensor - article
35 - TRB Open or short circuit in Pressure Sensor Test Turbo Pressure Sensor, check wiring, check connector
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
43 - STA No starter signal over 800 RPM starting Check Ignition Switch
51 - IDL No "IDL" or A/C signal during testing Check throttle position sensor - article, A/C switch, accelerator cable
52 - KNK Open or short circuit in Knock Sensor Check for broken/brittle wire, 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, (not applicable to 185), 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
71 - EGR EGR gas temp below acceptable level Check EGR system, (Valve/VSV/Hose/Temp). Not applicable for cars outside of Canada


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.