If you can check your engine fault codes then you can do this – delete all faults from engine, then start your car and turn steering wheel to left and right. As there is lot of cables in this place, then can be different fault codes – data bus, sensors, power etc. You need to check if the fastening of the bundle of cables is intact and that they have not been rubbing against the steering shaft. You can check it with a mirror that is attached to a long rod. Check in engine bay under the battery if the steering shaft frictions the cables coming from Engine Control Module. Different fault codes when ECU cables has broken by steering shaft One reason can be broken cable fastening – the cable has moved from its correct position and rubs against other parts. This plate is located inside the gearbox, but replacing it is not difficult.ħ. TCM is located on the right side of shifter assembly, near the passenger legs.Ħ. You can resolder them for “just in case” as well. If you can see any circles on the solderings then resolder them. Disassemble the TCM and use magnifier to check the solderings of both plugs.
The solderings of the plugs of Transmission Control Module can crack with time. Then the outcome is again P0702 and limp mode. Also check if the cables are fine – with time the isolation can crack and cables can go to short circuit. It is easy to check the plug – look under the car and check if the plug is oily. Once oily, the plugs have bad electrical connection and transmission goes into limp mode and starts showing fault codes. Gearbox plug adapter, OEM 68021352AA Transmission plug adapter is located under the car and often starts leaking oil. To avoid starting problems in future, you should still change the battery soon.Ĥ.
This upgrade won’t make your battery better, but does not allow TCM to go into limp mode cause of undervoltage.
If the limp mode is caused by bad battery then you can upgrade the Transmission Control Module software at your dealer. You should check the battery and cables from both ends, battery and car. Your Jeep Grand Cherokee’s transmission can go into limp mode if you are using a weak battery. You have to replace the Gear Shifter Lever PCB Board.ģ. Until you can’t start your car on a cold winter morning as you battery is still weak…Ģ. Upgrading software does not make your battery new, it just does not let your car to go into limp mode for this fault.
You can also avoid battery fault by asking Jeep dealer to upgrade TCM software. If adapter is fine, then your car has a weak battery and you need to change it. About gearbox plug adapter you can look at tip 4.
With this code there can be 2 reasons – gearbox plug adapter or weak battery. This fault is very common, it means that transmission solenoids are not getting enough power. P2602 Solenoid Valve: power supply Value/signal outside range. It is possible to fix the gear shifter, but you would need hard-to-get microchips and it can break again soon due to oxidation.īelow you can find some most common faults that may be related to fault code P0702. Addition to those mentioned, also P1242, P2210 and P2212may occur due to data communication errors which result from broken Jeep gear shifter (mostly), Transmission Control Module (TCM) or wiring between Engine Control Unit (ECU) and TCM. There are a lot of fault codes that indicate to Jeep Grand Cherokee WJ transmission malfunctions and limp mode.