When my 1996 Grand Cherokee is hooked to code reader it says Injector Circuit/open cylinder what does this mean and how do I fix it

'year make model' in all question please.

P0203 OBD-II Trouble Code: Injector Circuit Malfunction

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The P0203 is a diagnostic trouble code that is set when the engine control module (ECM) has detected a fault in the injector circuit for cylinder 3. The ECM ...

P0203 Code: Injector Circuit / Open - Cylinder 3 - CarParts.com

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Diagnostic trouble code (DTC) P0203 stands for "Injector Circuit/Open - Cylinder 3." The powertrain control module (PCM) may set this code if it ...
Nov 11, 2021 · Uploaded by The Flat Rate Mechanic

Error Code P0203: Cylinder 3 Injector Circuit Malfunction

https://autoservicecosts.com > obd2-codes > p0203
Error Code P0203 is defined as Cylinder 3 Injector Circuit Malfunction. This code means the PCM (powertrain control module, also known as ECM or engine ..

code p 0307 is misfiring on no 7 cylinder ====causes --- engine mechanical fault ---wiring---ignition/ fuel system--injector --ECT/MAF sensor---ECM
look for low fuel pressure or ignition control module

P0202 means that there is a problem in the fuel injector circuit #2. You will need to measure the wiring from the injector to the PCM for continuity and the other side for 12V (with ignition in on. Be aware that the ASD relay (auto shutdown relay) will deenergize after some seconds when the engine is not started and you will loose the 12V. Since you only have one injector code, the 12V is most probably OK. I would swap injector #2 with an other (easy to reach) injector and see if the complaint will follow to the other cylinder. If it does, then the injector is bad and need to be changed. If it doesn't, then there is a good change that the driver in the PCM is bad and the PCM needs to be changed in that case.

P0452 means fuel tank pressure sensor circuit low pressure. Possible symptoms:
- Fuel Tank Pressure Sensor harness is open or shorted
- Fuel Tank Pressure Sensor circuit poor electrical connection
- Faulty Fuel Tank Pressure Sensor
The code 0305 means cylinder 5 misfire detected. Possible symptoms:
- Faulty spark plug 5
- Clogged or faulty fuel injector 5
- Faulty ignition coil 5
- Fuel injector 5 harness is open or shorted
- Fuel injector 5 circuit poor electrical connection
- Ignition coil 5 harness is open or shorted
- Ignition coil 5 circuit poor electrical connection
- Insufficient cylinder 5 compression
- Incorrect fuel pressure
- Intake air leak

Read more: http://engine-codes.com/p0305_pontiac.html#ixzz2d8l8VHWe
Read more: http://engine-codes.com/p0452_pontiac.html#ixzz2d8kXRa8w

P0302 TOYOTA - Cylinder 2 Misfire Detectedhttp://engine-codes.com/p0302_toyota.htmlForum CodePossible causes- Faulty spark plug 2
- Faulty ignition coil 2
- Ignition coil 2 harness is open or shorted
- Ignition coil 2 poor electrical connection
- Clogged or faulty fuel injector 2
- Injector 2 harness is open or shorted
- Injector 2 poor electrical connection
- Improper spark plug 2
- Insufficient cylinder 2 compression
- Incorrect fuel pressure
- Intake air leak
P0135 - O2 Sensor Heater Circuit Malfunction Bank 1 Sensor 1http://engine-codes.com/p0135.htmlForum CodePossible causes- Faulty Heated Oxygen Sensor (H2OS) Bank 1 Sensor 1 circuit
- Heated Oxygen Sensor (H2OS) Bank 1 Sensor 1 circuit open shorted to ground
- Heated Oxygen Sensor (H2OS) Bank 1 Sensor 1 circuit poor electrical connection
- Heated Oxygen Sensor (H2OS) Bank 1 Sensor 1 circuit fuse
- Faulty Engine Control Module (ECM)
Tech notes The code means that there is a problem with the heater element circuit of the heated oxygen sensor. The Engine Control Module (ECM) monitors how long it take the sensor to warm up and start sending an adequate signal. The code means the the sensor is taking too long to warm up. Replacing the O2 Sensor 1 usually takes care of the problem
P1705 TOYOTA - Direct Clutch Speed Sensor Circuit Fault.
This is related to the sensor that gives info about the slippage rate o fthe transmisssion to the Transmission Control Module..

The evidence suggests that you do indeed have a bad fuel injector. Inspect the wiring to make sure you don't just have a poor electrical connection there - then if that looks good replace the injector.

CODE 27 - Injector Control Circuit, output driver does not respond properly to the control signal

Code 27 MIL light options: OBDII
P0201 - Injector #1 Control Circuit
P0202 - Injector #2 Control Circuit
P0203 - Injector #3 Control Circuit
P0204 - Injector #4 Control Circuit
P0205 - Injector #5 Control Circuit
P0206 - Injector #6 Control Circuit

CODE 43 - Cylinder Misfire, or Ignition Primary Circuit

CODE $# MIL options: OBDII
P0300 - Multiple Cylinder Misfire
P0301 - Cylinder #1 Misfire
P0302 - Cylinder #2 Misfire
P0303 - Cylinder #3 Misfire
P0304 - Cylinder #4 Misfire
P0305 - Cylinder #5 Misfire
P0306 - Cylinder #6 Misfire
P0351 - Ignition Coil #1 Primary Circuit
P0352 - Ignition Coil #2 Primary Circuit
P0353 - Ignition Coil #3 Primary Circuit

tinyp78 has it right if it has the check engine light on then don't run it as it will damage the catalytic converter, as well if the injector fails and exlodes the parts can go into engine and damage a valve or cylinder.

Injector # 4 Control Circuit.
Injector # 4 or INJ 4 injector bank output driver stage does not respond properly to the control signal.

douple ck all the ground wiresto engine,trans bell housing ,battery or frame/firewall look for any that may have separated from any pack of wires or broken off eyelets then thightnen all points,,.these grounds are very important to comp/injection controls and can cause a multi code problem like yours.